KILLED
proof of input_dan5Anqs7b.trs
# AProVE Commit ID: aff8ecad908e01718a4c36e68d2e55d5e0f16e15 fuhs 20220216 unpublished


The Runtime Complexity (parallel-innermost) of the given CpxTRS could be proven to be BOUNDS(1, INF).

(0) CpxTRS
(1) RenamingProof [BOTH BOUNDS(ID, ID), 0 ms]
(2) CpxTRS
(3) RelTrsToTrsProof [UPPER BOUND(ID), 0 ms]
(4) CpxTRS
(5) RelTrsToWeightedTrsProof [UPPER BOUND(ID), 0 ms]
(6) CpxWeightedTrs
    (7) TypeInferenceProof [BOTH BOUNDS(ID, ID), 0 ms]
    (8) CpxTypedWeightedTrs
    (9) CompletionProof [UPPER BOUND(ID), 0 ms]
    (10) CpxTypedWeightedCompleteTrs
        (11) NarrowingProof [BOTH BOUNDS(ID, ID), 0 ms]
        (12) CpxTypedWeightedCompleteTrs
        (13) CpxTypedWeightedTrsToRntsProof [UPPER BOUND(ID), 0 ms]
        (14) CpxRNTS
        (15) SimplificationProof [BOTH BOUNDS(ID, ID), 0 ms]
        (16) CpxRNTS
    (17) CompletionProof [UPPER BOUND(ID), 0 ms]
    (18) CpxTypedWeightedCompleteTrs
        (19) CpxTypedWeightedTrsToRntsProof [UPPER BOUND(ID), 0 ms]
        (20) CpxRNTS
(21) CpxTrsToCdtProof [UPPER BOUND(ID), 0 ms]
(22) CdtProblem
    (23) CdtLeafRemovalProof [BOTH BOUNDS(ID, ID), 0 ms]
    (24) CdtProblem
    (25) CdtNarrowingProof [BOTH BOUNDS(ID, ID), 3 ms]
    (26) CdtProblem
    (27) CdtLeafRemovalProof [BOTH BOUNDS(ID, ID), 0 ms]
    (28) CdtProblem
    (29) CdtRhsSimplificationProcessorProof [BOTH BOUNDS(ID, ID), 0 ms]
    (30) CdtProblem
    (31) CdtNarrowingProof [BOTH BOUNDS(ID, ID), 1 ms]
    (32) CdtProblem
    (33) CdtLeafRemovalProof [BOTH BOUNDS(ID, ID), 0 ms]
    (34) CdtProblem
    (35) CdtRhsSimplificationProcessorProof [BOTH BOUNDS(ID, ID), 0 ms]
    (36) CdtProblem
    (37) CdtNarrowingProof [BOTH BOUNDS(ID, ID), 0 ms]
    (38) CdtProblem
    (39) CdtLeafRemovalProof [BOTH BOUNDS(ID, ID), 0 ms]
    (40) CdtProblem
    (41) CdtRhsSimplificationProcessorProof [BOTH BOUNDS(ID, ID), 0 ms]
    (42) CdtProblem
    (43) CdtNarrowingProof [BOTH BOUNDS(ID, ID), 0 ms]
    (44) CdtProblem
    (45) CdtLeafRemovalProof [BOTH BOUNDS(ID, ID), 0 ms]
    (46) CdtProblem
    (47) CdtRhsSimplificationProcessorProof [BOTH BOUNDS(ID, ID), 4 ms]
    (48) CdtProblem
    (49) CdtNarrowingProof [BOTH BOUNDS(ID, ID), 0 ms]
    (50) CdtProblem
    (51) CdtLeafRemovalProof [BOTH BOUNDS(ID, ID), 0 ms]
    (52) CdtProblem
    (53) CdtRhsSimplificationProcessorProof [BOTH BOUNDS(ID, ID), 0 ms]
    (54) CdtProblem
    (55) CdtNarrowingProof [BOTH BOUNDS(ID, ID), 46 ms]
    (56) CdtProblem
    (57) CdtRhsSimplificationProcessorProof [BOTH BOUNDS(ID, ID), 0 ms]
    (58) CdtProblem
    (59) CdtNarrowingProof [BOTH BOUNDS(ID, ID), 12 ms]
    (60) CdtProblem
    (61) CdtRhsSimplificationProcessorProof [BOTH BOUNDS(ID, ID), 0 ms]
    (62) CdtProblem
    (63) CdtNarrowingProof [BOTH BOUNDS(ID, ID), 0 ms]
    (64) CdtProblem
    (65) CdtRhsSimplificationProcessorProof [BOTH BOUNDS(ID, ID), 0 ms]
    (66) CdtProblem
    (67) CdtNarrowingProof [BOTH BOUNDS(ID, ID), 60 ms]
    (68) CdtProblem
    (69) CdtRhsSimplificationProcessorProof [BOTH BOUNDS(ID, ID), 0 ms]
    (70) CdtProblem
    (71) CdtNarrowingProof [BOTH BOUNDS(ID, ID), 0 ms]
    (72) CdtProblem
    (73) CdtRhsSimplificationProcessorProof [BOTH BOUNDS(ID, ID), 0 ms]
    (74) CdtProblem
    (75) CdtNarrowingProof [BOTH BOUNDS(ID, ID), 0 ms]
    (76) CdtProblem
    (77) CdtRhsSimplificationProcessorProof [BOTH BOUNDS(ID, ID), 0 ms]
    (78) CdtProblem
    (79) CdtNarrowingProof [BOTH BOUNDS(ID, ID), 22 ms]
    (80) CdtProblem
    (81) CdtLeafRemovalProof [BOTH BOUNDS(ID, ID), 0 ms]
    (82) CdtProblem
    (83) CdtRhsSimplificationProcessorProof [BOTH BOUNDS(ID, ID), 13 ms]
    (84) CdtProblem
    (85) CdtNarrowingProof [BOTH BOUNDS(ID, ID), 53 ms]
    (86) CdtProblem
    (87) CdtLeafRemovalProof [BOTH BOUNDS(ID, ID), 0 ms]
    (88) CdtProblem
    (89) CdtRhsSimplificationProcessorProof [BOTH BOUNDS(ID, ID), 0 ms]
    (90) CdtProblem
    (91) CdtNarrowingProof [BOTH BOUNDS(ID, ID), 0 ms]
    (92) CdtProblem
    (93) CdtLeafRemovalProof [BOTH BOUNDS(ID, ID), 0 ms]
    (94) CdtProblem
    (95) CdtRhsSimplificationProcessorProof [BOTH BOUNDS(ID, ID), 0 ms]
    (96) CdtProblem
    (97) CdtForwardInstantiationProof [BOTH BOUNDS(ID, ID), 391 ms]
    (98) CdtProblem
    (99) CdtRhsSimplificationProcessorProof [BOTH BOUNDS(ID, ID), 30 ms]
    (100) CdtProblem
    (101) CdtForwardInstantiationProof [BOTH BOUNDS(ID, ID), 134 ms]
    (102) CdtProblem
    (103) CdtNarrowingProof [BOTH BOUNDS(ID, ID), 0 ms]
    (104) CdtProblem
    (105) CdtLeafRemovalProof [BOTH BOUNDS(ID, ID), 17 ms]
    (106) CdtProblem
    (107) CdtRhsSimplificationProcessorProof [BOTH BOUNDS(ID, ID), 0 ms]
    (108) CdtProblem
    (109) CdtNarrowingProof [BOTH BOUNDS(ID, ID), 16.0 s]
    (110) CdtProblem
    (111) CdtNarrowingProof [BOTH BOUNDS(ID, ID), 16.6 s]
    (112) CdtProblem
    (113) CdtRhsSimplificationProcessorProof [BOTH BOUNDS(ID, ID), 0 ms]
    (114) CdtProblem
    (115) CdtForwardInstantiationProof [BOTH BOUNDS(ID, ID), 312 ms]
    (116) CdtProblem
    (117) CdtRhsSimplificationProcessorProof [BOTH BOUNDS(ID, ID), 0 ms]
    (118) CdtProblem
    (119) CdtForwardInstantiationProof [BOTH BOUNDS(ID, ID), 872 ms]
    (120) CdtProblem
    (121) CdtLeafRemovalProof [BOTH BOUNDS(ID, ID), 15 ms]
    (122) CdtProblem
    (123) CdtForwardInstantiationProof [BOTH BOUNDS(ID, ID), 3646 ms]
    (124) CdtProblem


----------------------------------------

(0)
Obligation:
The Runtime Complexity (parallel-innermost) of the given CpxTRS could be proven to be BOUNDS(1, INF).


The TRS R consists of the following rules:

   a__first(0, X) -> nil
   a__first(s(X), cons(Y, Z)) -> cons(mark(Y), first(X, Z))
   a__from(X) -> cons(mark(X), from(s(X)))
   mark(first(X1, X2)) -> a__first(mark(X1), mark(X2))
   mark(from(X)) -> a__from(mark(X))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(X)) -> s(mark(X))
   mark(cons(X1, X2)) -> cons(mark(X1), X2)
   a__first(X1, X2) -> first(X1, X2)
   a__from(X) -> from(X)

S is empty.
Rewrite Strategy: PARALLEL_INNERMOST
----------------------------------------

(1) RenamingProof (BOTH BOUNDS(ID, ID))
Renamed function symbols to avoid clashes with predefined symbol.
----------------------------------------

(2)
Obligation:
The Runtime Complexity (parallel-innermost) of the given CpxTRS could be proven to be BOUNDS(1, INF).


The TRS R consists of the following rules:

   a__first(0', X) -> nil
   a__first(s(X), cons(Y, Z)) -> cons(mark(Y), first(X, Z))
   a__from(X) -> cons(mark(X), from(s(X)))
   mark(first(X1, X2)) -> a__first(mark(X1), mark(X2))
   mark(from(X)) -> a__from(mark(X))
   mark(0') -> 0'
   mark(nil) -> nil
   mark(s(X)) -> s(mark(X))
   mark(cons(X1, X2)) -> cons(mark(X1), X2)
   a__first(X1, X2) -> first(X1, X2)
   a__from(X) -> from(X)

S is empty.
Rewrite Strategy: PARALLEL_INNERMOST
----------------------------------------

(3) RelTrsToTrsProof (UPPER BOUND(ID))
transformed relative TRS to TRS
----------------------------------------

(4)
Obligation:
The Runtime Complexity (parallel-innermost) of the given CpxTRS could be proven to be BOUNDS(1, INF).


The TRS R consists of the following rules:

   a__first(0, X) -> nil
   a__first(s(X), cons(Y, Z)) -> cons(mark(Y), first(X, Z))
   a__from(X) -> cons(mark(X), from(s(X)))
   mark(first(X1, X2)) -> a__first(mark(X1), mark(X2))
   mark(from(X)) -> a__from(mark(X))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(X)) -> s(mark(X))
   mark(cons(X1, X2)) -> cons(mark(X1), X2)
   a__first(X1, X2) -> first(X1, X2)
   a__from(X) -> from(X)

S is empty.
Rewrite Strategy: PARALLEL_INNERMOST
----------------------------------------

(5) RelTrsToWeightedTrsProof (UPPER BOUND(ID))
Transformed relative TRS to weighted TRS
----------------------------------------

(6)
Obligation:
The Runtime Complexity (innermost) of the given CpxWeightedTrs could be proven to be BOUNDS(1, INF).


The TRS R consists of the following rules:

   a__first(0, X) -> nil [1]
   a__first(s(X), cons(Y, Z)) -> cons(mark(Y), first(X, Z)) [1]
   a__from(X) -> cons(mark(X), from(s(X))) [1]
   mark(first(X1, X2)) -> a__first(mark(X1), mark(X2)) [1]
   mark(from(X)) -> a__from(mark(X)) [1]
   mark(0) -> 0 [1]
   mark(nil) -> nil [1]
   mark(s(X)) -> s(mark(X)) [1]
   mark(cons(X1, X2)) -> cons(mark(X1), X2) [1]
   a__first(X1, X2) -> first(X1, X2) [1]
   a__from(X) -> from(X) [1]

Rewrite Strategy: INNERMOST
----------------------------------------

(7) TypeInferenceProof (BOTH BOUNDS(ID, ID))
Infered types.
----------------------------------------

(8)
Obligation:
Runtime Complexity Weighted TRS with Types.
The TRS R consists of the following rules:

   a__first(0, X) -> nil [1]
   a__first(s(X), cons(Y, Z)) -> cons(mark(Y), first(X, Z)) [1]
   a__from(X) -> cons(mark(X), from(s(X))) [1]
   mark(first(X1, X2)) -> a__first(mark(X1), mark(X2)) [1]
   mark(from(X)) -> a__from(mark(X)) [1]
   mark(0) -> 0 [1]
   mark(nil) -> nil [1]
   mark(s(X)) -> s(mark(X)) [1]
   mark(cons(X1, X2)) -> cons(mark(X1), X2) [1]
   a__first(X1, X2) -> first(X1, X2) [1]
   a__from(X) -> from(X) [1]

The TRS has the following type information:
a__first :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from
0 :: 0:nil:s:cons:first:from
nil :: 0:nil:s:cons:first:from
s :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from
cons :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from
mark :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from
first :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from
a__from :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from
from :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from

Rewrite Strategy: INNERMOST
----------------------------------------

(9) CompletionProof (UPPER BOUND(ID))
The transformation into a RNTS is sound, since:

(a) The obligation is a constructor system where every type has a constant constructor,

(b) The following defined symbols do not have to be completely defined, as they can never occur inside other defined symbols:
none

(c) The following functions are completely defined:

   mark_1
   a__from_1
   a__first_2

Due to the following rules being added:
none

And the following fresh constants: none

----------------------------------------

(10)
Obligation:
Runtime Complexity Weighted TRS where critical functions are completely defined. The underlying TRS is:

Runtime Complexity Weighted TRS with Types.
The TRS R consists of the following rules:

   a__first(0, X) -> nil [1]
   a__first(s(X), cons(Y, Z)) -> cons(mark(Y), first(X, Z)) [1]
   a__from(X) -> cons(mark(X), from(s(X))) [1]
   mark(first(X1, X2)) -> a__first(mark(X1), mark(X2)) [1]
   mark(from(X)) -> a__from(mark(X)) [1]
   mark(0) -> 0 [1]
   mark(nil) -> nil [1]
   mark(s(X)) -> s(mark(X)) [1]
   mark(cons(X1, X2)) -> cons(mark(X1), X2) [1]
   a__first(X1, X2) -> first(X1, X2) [1]
   a__from(X) -> from(X) [1]

The TRS has the following type information:
a__first :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from
0 :: 0:nil:s:cons:first:from
nil :: 0:nil:s:cons:first:from
s :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from
cons :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from
mark :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from
first :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from
a__from :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from
from :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from

Rewrite Strategy: INNERMOST
----------------------------------------

(11) NarrowingProof (BOTH BOUNDS(ID, ID))
Narrowed the inner basic terms of all right-hand sides by a single narrowing step.
----------------------------------------

(12)
Obligation:
Runtime Complexity Weighted TRS where critical functions are completely defined. The underlying TRS is:

Runtime Complexity Weighted TRS with Types.
The TRS R consists of the following rules:

   a__first(0, X) -> nil [1]
   a__first(s(X), cons(Y, Z)) -> cons(mark(Y), first(X, Z)) [1]
   a__from(X) -> cons(mark(X), from(s(X))) [1]
   mark(first(X1, X2)) -> a__first(mark(X1), mark(X2)) [1]
   mark(from(first(X113, X213))) -> a__from(a__first(mark(X113), mark(X213))) [2]
   mark(from(from(X33))) -> a__from(a__from(mark(X33))) [2]
   mark(from(0)) -> a__from(0) [2]
   mark(from(nil)) -> a__from(nil) [2]
   mark(from(s(X34))) -> a__from(s(mark(X34))) [2]
   mark(from(cons(X114, X214))) -> a__from(cons(mark(X114), X214)) [2]
   mark(0) -> 0 [1]
   mark(nil) -> nil [1]
   mark(s(X)) -> s(mark(X)) [1]
   mark(cons(X1, X2)) -> cons(mark(X1), X2) [1]
   a__first(X1, X2) -> first(X1, X2) [1]
   a__from(X) -> from(X) [1]

The TRS has the following type information:
a__first :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from
0 :: 0:nil:s:cons:first:from
nil :: 0:nil:s:cons:first:from
s :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from
cons :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from
mark :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from
first :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from
a__from :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from
from :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from

Rewrite Strategy: INNERMOST
----------------------------------------

(13) CpxTypedWeightedTrsToRntsProof (UPPER BOUND(ID))
Transformed the TRS into an over-approximating RNTS by (improved) Size Abstraction.
The constant constructors are abstracted as follows:

   0 => 0
   nil => 1

----------------------------------------

(14)
Obligation:
Complexity RNTS consisting of the following rules:

   a__first(z, z') -{ 1 }-> 1 :|: z' = X, X >= 0, z = 0
   a__first(z, z') -{ 1 }-> 1 + X1 + X2 :|: X1 >= 0, X2 >= 0, z = X1, z' = X2
   a__first(z, z') -{ 1 }-> 1 + mark(Y) + (1 + X + Z) :|: Z >= 0, z = 1 + X, Y >= 0, X >= 0, z' = 1 + Y + Z
   a__from(z) -{ 1 }-> 1 + X :|: X >= 0, z = X
   a__from(z) -{ 1 }-> 1 + mark(X) + (1 + (1 + X)) :|: X >= 0, z = X
   mark(z) -{ 2 }-> a__from(a__from(mark(X33))) :|: X33 >= 0, z = 1 + (1 + X33)
   mark(z) -{ 2 }-> a__from(a__first(mark(X113), mark(X213))) :|: X113 >= 0, X213 >= 0, z = 1 + (1 + X113 + X213)
   mark(z) -{ 2 }-> a__from(1) :|: z = 1 + 1
   mark(z) -{ 2 }-> a__from(0) :|: z = 1 + 0
   mark(z) -{ 2 }-> a__from(1 + mark(X34)) :|: z = 1 + (1 + X34), X34 >= 0
   mark(z) -{ 2 }-> a__from(1 + mark(X114) + X214) :|: X114 >= 0, X214 >= 0, z = 1 + (1 + X114 + X214)
   mark(z) -{ 1 }-> a__first(mark(X1), mark(X2)) :|: X1 >= 0, X2 >= 0, z = 1 + X1 + X2
   mark(z) -{ 1 }-> 1 :|: z = 1
   mark(z) -{ 1 }-> 0 :|: z = 0
   mark(z) -{ 1 }-> 1 + mark(X) :|: z = 1 + X, X >= 0
   mark(z) -{ 1 }-> 1 + mark(X1) + X2 :|: X1 >= 0, X2 >= 0, z = 1 + X1 + X2


----------------------------------------

(15) SimplificationProof (BOTH BOUNDS(ID, ID))
Simplified the RNTS by moving equalities from the constraints into the right-hand sides.
----------------------------------------

(16)
Obligation:
Complexity RNTS consisting of the following rules:

   a__first(z, z') -{ 1 }-> 1 :|: z' >= 0, z = 0
   a__first(z, z') -{ 1 }-> 1 + z + z' :|: z >= 0, z' >= 0
   a__first(z, z') -{ 1 }-> 1 + mark(Y) + (1 + (z - 1) + Z) :|: Z >= 0, Y >= 0, z - 1 >= 0, z' = 1 + Y + Z
   a__from(z) -{ 1 }-> 1 + z :|: z >= 0
   a__from(z) -{ 1 }-> 1 + mark(z) + (1 + (1 + z)) :|: z >= 0
   mark(z) -{ 2 }-> a__from(a__from(mark(z - 2))) :|: z - 2 >= 0
   mark(z) -{ 2 }-> a__from(a__first(mark(X113), mark(X213))) :|: X113 >= 0, X213 >= 0, z = 1 + (1 + X113 + X213)
   mark(z) -{ 2 }-> a__from(1) :|: z = 1 + 1
   mark(z) -{ 2 }-> a__from(0) :|: z = 1 + 0
   mark(z) -{ 2 }-> a__from(1 + mark(z - 2)) :|: z - 2 >= 0
   mark(z) -{ 2 }-> a__from(1 + mark(X114) + X214) :|: X114 >= 0, X214 >= 0, z = 1 + (1 + X114 + X214)
   mark(z) -{ 1 }-> a__first(mark(X1), mark(X2)) :|: X1 >= 0, X2 >= 0, z = 1 + X1 + X2
   mark(z) -{ 1 }-> 1 :|: z = 1
   mark(z) -{ 1 }-> 0 :|: z = 0
   mark(z) -{ 1 }-> 1 + mark(z - 1) :|: z - 1 >= 0
   mark(z) -{ 1 }-> 1 + mark(X1) + X2 :|: X1 >= 0, X2 >= 0, z = 1 + X1 + X2


----------------------------------------

(17) CompletionProof (UPPER BOUND(ID))
The TRS is a completely defined constructor system, as every type has a constant constructor and the following rules were added:
none

And the following fresh constants: none

----------------------------------------

(18)
Obligation:
Runtime Complexity Weighted TRS where all functions are completely defined. The underlying TRS is:

Runtime Complexity Weighted TRS with Types.
The TRS R consists of the following rules:

   a__first(0, X) -> nil [1]
   a__first(s(X), cons(Y, Z)) -> cons(mark(Y), first(X, Z)) [1]
   a__from(X) -> cons(mark(X), from(s(X))) [1]
   mark(first(X1, X2)) -> a__first(mark(X1), mark(X2)) [1]
   mark(from(X)) -> a__from(mark(X)) [1]
   mark(0) -> 0 [1]
   mark(nil) -> nil [1]
   mark(s(X)) -> s(mark(X)) [1]
   mark(cons(X1, X2)) -> cons(mark(X1), X2) [1]
   a__first(X1, X2) -> first(X1, X2) [1]
   a__from(X) -> from(X) [1]

The TRS has the following type information:
a__first :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from
0 :: 0:nil:s:cons:first:from
nil :: 0:nil:s:cons:first:from
s :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from
cons :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from
mark :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from
first :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from
a__from :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from
from :: 0:nil:s:cons:first:from -> 0:nil:s:cons:first:from

Rewrite Strategy: INNERMOST
----------------------------------------

(19) CpxTypedWeightedTrsToRntsProof (UPPER BOUND(ID))
Transformed the TRS into an over-approximating RNTS by (improved) Size Abstraction.
The constant constructors are abstracted as follows:

   0 => 0
   nil => 1

----------------------------------------

(20)
Obligation:
Complexity RNTS consisting of the following rules:

   a__first(z, z') -{ 1 }-> 1 :|: z' = X, X >= 0, z = 0
   a__first(z, z') -{ 1 }-> 1 + X1 + X2 :|: X1 >= 0, X2 >= 0, z = X1, z' = X2
   a__first(z, z') -{ 1 }-> 1 + mark(Y) + (1 + X + Z) :|: Z >= 0, z = 1 + X, Y >= 0, X >= 0, z' = 1 + Y + Z
   a__from(z) -{ 1 }-> 1 + X :|: X >= 0, z = X
   a__from(z) -{ 1 }-> 1 + mark(X) + (1 + (1 + X)) :|: X >= 0, z = X
   mark(z) -{ 1 }-> a__from(mark(X)) :|: z = 1 + X, X >= 0
   mark(z) -{ 1 }-> a__first(mark(X1), mark(X2)) :|: X1 >= 0, X2 >= 0, z = 1 + X1 + X2
   mark(z) -{ 1 }-> 1 :|: z = 1
   mark(z) -{ 1 }-> 0 :|: z = 0
   mark(z) -{ 1 }-> 1 + mark(X) :|: z = 1 + X, X >= 0
   mark(z) -{ 1 }-> 1 + mark(X1) + X2 :|: X1 >= 0, X2 >= 0, z = 1 + X1 + X2

Only complete derivations are relevant for the runtime complexity.

----------------------------------------

(21) CpxTrsToCdtProof (UPPER BOUND(ID))
Converted Cpx (relative) TRS with rewrite strategy PARALLEL_INNERMOST to CDT
----------------------------------------

(22)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(0, z0) -> c
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FIRST(z0, z1) -> c2
   A__FROM(z0) -> c3(MARK(z0))
   A__FROM(z0) -> c4
   MARK(first(z0, z1)) -> c5(A__FIRST(mark(z0), mark(z1)), MARK(z0))
   MARK(first(z0, z1)) -> c6(A__FIRST(mark(z0), mark(z1)), MARK(z1))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(0) -> c8
   MARK(nil) -> c9
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
S tuples:
   A__FIRST(0, z0) -> c
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FIRST(z0, z1) -> c2
   A__FROM(z0) -> c3(MARK(z0))
   A__FROM(z0) -> c4
   MARK(first(z0, z1)) -> c5(A__FIRST(mark(z0), mark(z1)), MARK(z0))
   MARK(first(z0, z1)) -> c6(A__FIRST(mark(z0), mark(z1)), MARK(z1))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(0) -> c8
   MARK(nil) -> c9
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c, c1_1, c2, c3_1, c4, c5_2, c6_2, c7_2, c8, c9, c10_1, c11_1


----------------------------------------

(23) CdtLeafRemovalProof (BOTH BOUNDS(ID, ID))
Removed 5 trailing nodes:
   A__FIRST(z0, z1) -> c2
   MARK(0) -> c8
   A__FROM(z0) -> c4
   MARK(nil) -> c9
   A__FIRST(0, z0) -> c

----------------------------------------

(24)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(first(z0, z1)) -> c5(A__FIRST(mark(z0), mark(z1)), MARK(z0))
   MARK(first(z0, z1)) -> c6(A__FIRST(mark(z0), mark(z1)), MARK(z1))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(first(z0, z1)) -> c5(A__FIRST(mark(z0), mark(z1)), MARK(z0))
   MARK(first(z0, z1)) -> c6(A__FIRST(mark(z0), mark(z1)), MARK(z1))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c5_2, c6_2, c7_2, c10_1, c11_1


----------------------------------------

(25) CdtNarrowingProof (BOTH BOUNDS(ID, ID))
Use narrowing to replace MARK(first(z0, z1)) -> c5(A__FIRST(mark(z0), mark(z1)), MARK(z0)) by 
   MARK(first(x0, first(z0, z1))) -> c5(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(x0))
   MARK(first(x0, from(z0))) -> c5(A__FIRST(mark(x0), a__from(mark(z0))), MARK(x0))
   MARK(first(x0, 0)) -> c5(A__FIRST(mark(x0), 0), MARK(x0))
   MARK(first(x0, nil)) -> c5(A__FIRST(mark(x0), nil), MARK(x0))
   MARK(first(x0, s(z0))) -> c5(A__FIRST(mark(x0), s(mark(z0))), MARK(x0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(0, x1)) -> c5(A__FIRST(0, mark(x1)), MARK(0))
   MARK(first(nil, x1)) -> c5(A__FIRST(nil, mark(x1)), MARK(nil))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(cons(z0, z1), x1)) -> c5(A__FIRST(cons(mark(z0), z1), mark(x1)), MARK(cons(z0, z1)))

----------------------------------------

(26)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(first(z0, z1)) -> c6(A__FIRST(mark(z0), mark(z1)), MARK(z1))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, first(z0, z1))) -> c5(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(x0))
   MARK(first(x0, from(z0))) -> c5(A__FIRST(mark(x0), a__from(mark(z0))), MARK(x0))
   MARK(first(x0, 0)) -> c5(A__FIRST(mark(x0), 0), MARK(x0))
   MARK(first(x0, nil)) -> c5(A__FIRST(mark(x0), nil), MARK(x0))
   MARK(first(x0, s(z0))) -> c5(A__FIRST(mark(x0), s(mark(z0))), MARK(x0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(0, x1)) -> c5(A__FIRST(0, mark(x1)), MARK(0))
   MARK(first(nil, x1)) -> c5(A__FIRST(nil, mark(x1)), MARK(nil))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(cons(z0, z1), x1)) -> c5(A__FIRST(cons(mark(z0), z1), mark(x1)), MARK(cons(z0, z1)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(first(z0, z1)) -> c6(A__FIRST(mark(z0), mark(z1)), MARK(z1))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, first(z0, z1))) -> c5(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(x0))
   MARK(first(x0, from(z0))) -> c5(A__FIRST(mark(x0), a__from(mark(z0))), MARK(x0))
   MARK(first(x0, 0)) -> c5(A__FIRST(mark(x0), 0), MARK(x0))
   MARK(first(x0, nil)) -> c5(A__FIRST(mark(x0), nil), MARK(x0))
   MARK(first(x0, s(z0))) -> c5(A__FIRST(mark(x0), s(mark(z0))), MARK(x0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(0, x1)) -> c5(A__FIRST(0, mark(x1)), MARK(0))
   MARK(first(nil, x1)) -> c5(A__FIRST(nil, mark(x1)), MARK(nil))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(cons(z0, z1), x1)) -> c5(A__FIRST(cons(mark(z0), z1), mark(x1)), MARK(cons(z0, z1)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c6_2, c7_2, c10_1, c11_1, c5_2


----------------------------------------

(27) CdtLeafRemovalProof (BOTH BOUNDS(ID, ID))
Removed 2 trailing nodes:
   MARK(first(nil, x1)) -> c5(A__FIRST(nil, mark(x1)), MARK(nil))
   MARK(first(0, x1)) -> c5(A__FIRST(0, mark(x1)), MARK(0))

----------------------------------------

(28)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(first(z0, z1)) -> c6(A__FIRST(mark(z0), mark(z1)), MARK(z1))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, first(z0, z1))) -> c5(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(x0))
   MARK(first(x0, from(z0))) -> c5(A__FIRST(mark(x0), a__from(mark(z0))), MARK(x0))
   MARK(first(x0, 0)) -> c5(A__FIRST(mark(x0), 0), MARK(x0))
   MARK(first(x0, nil)) -> c5(A__FIRST(mark(x0), nil), MARK(x0))
   MARK(first(x0, s(z0))) -> c5(A__FIRST(mark(x0), s(mark(z0))), MARK(x0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(cons(z0, z1), x1)) -> c5(A__FIRST(cons(mark(z0), z1), mark(x1)), MARK(cons(z0, z1)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(first(z0, z1)) -> c6(A__FIRST(mark(z0), mark(z1)), MARK(z1))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, first(z0, z1))) -> c5(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(x0))
   MARK(first(x0, from(z0))) -> c5(A__FIRST(mark(x0), a__from(mark(z0))), MARK(x0))
   MARK(first(x0, 0)) -> c5(A__FIRST(mark(x0), 0), MARK(x0))
   MARK(first(x0, nil)) -> c5(A__FIRST(mark(x0), nil), MARK(x0))
   MARK(first(x0, s(z0))) -> c5(A__FIRST(mark(x0), s(mark(z0))), MARK(x0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(cons(z0, z1), x1)) -> c5(A__FIRST(cons(mark(z0), z1), mark(x1)), MARK(cons(z0, z1)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c6_2, c7_2, c10_1, c11_1, c5_2


----------------------------------------

(29) CdtRhsSimplificationProcessorProof (BOTH BOUNDS(ID, ID))
Removed 4 trailing tuple parts
----------------------------------------

(30)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(first(z0, z1)) -> c6(A__FIRST(mark(z0), mark(z1)), MARK(z1))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, first(z0, z1))) -> c5(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(x0))
   MARK(first(x0, from(z0))) -> c5(A__FIRST(mark(x0), a__from(mark(z0))), MARK(x0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(first(z0, z1)) -> c6(A__FIRST(mark(z0), mark(z1)), MARK(z1))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, first(z0, z1))) -> c5(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(x0))
   MARK(first(x0, from(z0))) -> c5(A__FIRST(mark(x0), a__from(mark(z0))), MARK(x0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c6_2, c7_2, c10_1, c11_1, c5_2, c5_1


----------------------------------------

(31) CdtNarrowingProof (BOTH BOUNDS(ID, ID))
Use narrowing to replace MARK(first(z0, z1)) -> c6(A__FIRST(mark(z0), mark(z1)), MARK(z1)) by 
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, 0)) -> c6(A__FIRST(mark(x0), 0), MARK(0))
   MARK(first(x0, nil)) -> c6(A__FIRST(mark(x0), nil), MARK(nil))
   MARK(first(x0, s(z0))) -> c6(A__FIRST(mark(x0), s(mark(z0))), MARK(s(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(0, x1)) -> c6(A__FIRST(0, mark(x1)), MARK(x1))
   MARK(first(nil, x1)) -> c6(A__FIRST(nil, mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(A__FIRST(cons(mark(z0), z1), mark(x1)), MARK(x1))

----------------------------------------

(32)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, first(z0, z1))) -> c5(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(x0))
   MARK(first(x0, from(z0))) -> c5(A__FIRST(mark(x0), a__from(mark(z0))), MARK(x0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, 0)) -> c6(A__FIRST(mark(x0), 0), MARK(0))
   MARK(first(x0, nil)) -> c6(A__FIRST(mark(x0), nil), MARK(nil))
   MARK(first(x0, s(z0))) -> c6(A__FIRST(mark(x0), s(mark(z0))), MARK(s(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(0, x1)) -> c6(A__FIRST(0, mark(x1)), MARK(x1))
   MARK(first(nil, x1)) -> c6(A__FIRST(nil, mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(A__FIRST(cons(mark(z0), z1), mark(x1)), MARK(x1))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, first(z0, z1))) -> c5(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(x0))
   MARK(first(x0, from(z0))) -> c5(A__FIRST(mark(x0), a__from(mark(z0))), MARK(x0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, 0)) -> c6(A__FIRST(mark(x0), 0), MARK(0))
   MARK(first(x0, nil)) -> c6(A__FIRST(mark(x0), nil), MARK(nil))
   MARK(first(x0, s(z0))) -> c6(A__FIRST(mark(x0), s(mark(z0))), MARK(s(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(0, x1)) -> c6(A__FIRST(0, mark(x1)), MARK(x1))
   MARK(first(nil, x1)) -> c6(A__FIRST(nil, mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(A__FIRST(cons(mark(z0), z1), mark(x1)), MARK(x1))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_2, c5_1, c6_2


----------------------------------------

(33) CdtLeafRemovalProof (BOTH BOUNDS(ID, ID))
Removed 2 trailing nodes:
   MARK(first(x0, 0)) -> c6(A__FIRST(mark(x0), 0), MARK(0))
   MARK(first(x0, nil)) -> c6(A__FIRST(mark(x0), nil), MARK(nil))

----------------------------------------

(34)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, first(z0, z1))) -> c5(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(x0))
   MARK(first(x0, from(z0))) -> c5(A__FIRST(mark(x0), a__from(mark(z0))), MARK(x0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, s(z0))) -> c6(A__FIRST(mark(x0), s(mark(z0))), MARK(s(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(0, x1)) -> c6(A__FIRST(0, mark(x1)), MARK(x1))
   MARK(first(nil, x1)) -> c6(A__FIRST(nil, mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(A__FIRST(cons(mark(z0), z1), mark(x1)), MARK(x1))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, first(z0, z1))) -> c5(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(x0))
   MARK(first(x0, from(z0))) -> c5(A__FIRST(mark(x0), a__from(mark(z0))), MARK(x0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, s(z0))) -> c6(A__FIRST(mark(x0), s(mark(z0))), MARK(s(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(0, x1)) -> c6(A__FIRST(0, mark(x1)), MARK(x1))
   MARK(first(nil, x1)) -> c6(A__FIRST(nil, mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(A__FIRST(cons(mark(z0), z1), mark(x1)), MARK(x1))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_2, c5_1, c6_2


----------------------------------------

(35) CdtRhsSimplificationProcessorProof (BOTH BOUNDS(ID, ID))
Removed 4 trailing tuple parts
----------------------------------------

(36)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, first(z0, z1))) -> c5(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(x0))
   MARK(first(x0, from(z0))) -> c5(A__FIRST(mark(x0), a__from(mark(z0))), MARK(x0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, first(z0, z1))) -> c5(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(x0))
   MARK(first(x0, from(z0))) -> c5(A__FIRST(mark(x0), a__from(mark(z0))), MARK(x0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_2, c5_1, c6_2, c6_1


----------------------------------------

(37) CdtNarrowingProof (BOTH BOUNDS(ID, ID))
Use narrowing to replace MARK(first(x0, first(z0, z1))) -> c5(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(x0)) by 
   MARK(first(x0, first(x1, x2))) -> c5(A__FIRST(mark(x0), first(mark(x1), mark(x2))), MARK(x0))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(0, first(x1, x2))) -> c5(A__FIRST(0, a__first(mark(x1), mark(x2))), MARK(0))
   MARK(first(nil, first(x1, x2))) -> c5(A__FIRST(nil, a__first(mark(x1), mark(x2))), MARK(nil))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(A__FIRST(cons(mark(z0), z1), a__first(mark(x1), mark(x2))), MARK(cons(z0, z1)))

----------------------------------------

(38)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, from(z0))) -> c5(A__FIRST(mark(x0), a__from(mark(z0))), MARK(x0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, x2))) -> c5(A__FIRST(mark(x0), first(mark(x1), mark(x2))), MARK(x0))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(0, first(x1, x2))) -> c5(A__FIRST(0, a__first(mark(x1), mark(x2))), MARK(0))
   MARK(first(nil, first(x1, x2))) -> c5(A__FIRST(nil, a__first(mark(x1), mark(x2))), MARK(nil))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(A__FIRST(cons(mark(z0), z1), a__first(mark(x1), mark(x2))), MARK(cons(z0, z1)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, from(z0))) -> c5(A__FIRST(mark(x0), a__from(mark(z0))), MARK(x0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, x2))) -> c5(A__FIRST(mark(x0), first(mark(x1), mark(x2))), MARK(x0))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(0, first(x1, x2))) -> c5(A__FIRST(0, a__first(mark(x1), mark(x2))), MARK(0))
   MARK(first(nil, first(x1, x2))) -> c5(A__FIRST(nil, a__first(mark(x1), mark(x2))), MARK(nil))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(A__FIRST(cons(mark(z0), z1), a__first(mark(x1), mark(x2))), MARK(cons(z0, z1)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_2, c5_1, c6_2, c6_1


----------------------------------------

(39) CdtLeafRemovalProof (BOTH BOUNDS(ID, ID))
Removed 2 trailing nodes:
   MARK(first(nil, first(x1, x2))) -> c5(A__FIRST(nil, a__first(mark(x1), mark(x2))), MARK(nil))
   MARK(first(0, first(x1, x2))) -> c5(A__FIRST(0, a__first(mark(x1), mark(x2))), MARK(0))

----------------------------------------

(40)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, from(z0))) -> c5(A__FIRST(mark(x0), a__from(mark(z0))), MARK(x0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, x2))) -> c5(A__FIRST(mark(x0), first(mark(x1), mark(x2))), MARK(x0))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(A__FIRST(cons(mark(z0), z1), a__first(mark(x1), mark(x2))), MARK(cons(z0, z1)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, from(z0))) -> c5(A__FIRST(mark(x0), a__from(mark(z0))), MARK(x0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, x2))) -> c5(A__FIRST(mark(x0), first(mark(x1), mark(x2))), MARK(x0))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(A__FIRST(cons(mark(z0), z1), a__first(mark(x1), mark(x2))), MARK(cons(z0, z1)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_2, c5_1, c6_2, c6_1


----------------------------------------

(41) CdtRhsSimplificationProcessorProof (BOTH BOUNDS(ID, ID))
Removed 2 trailing tuple parts
----------------------------------------

(42)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, from(z0))) -> c5(A__FIRST(mark(x0), a__from(mark(z0))), MARK(x0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, from(z0))) -> c5(A__FIRST(mark(x0), a__from(mark(z0))), MARK(x0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_2, c5_1, c6_2, c6_1


----------------------------------------

(43) CdtNarrowingProof (BOTH BOUNDS(ID, ID))
Use narrowing to replace MARK(first(x0, from(z0))) -> c5(A__FIRST(mark(x0), a__from(mark(z0))), MARK(x0)) by 
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), from(mark(x1))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(0, from(x1))) -> c5(A__FIRST(0, a__from(mark(x1))), MARK(0))
   MARK(first(nil, from(x1))) -> c5(A__FIRST(nil, a__from(mark(x1))), MARK(nil))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(cons(z0, z1), from(x1))) -> c5(A__FIRST(cons(mark(z0), z1), a__from(mark(x1))), MARK(cons(z0, z1)))

----------------------------------------

(44)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), from(mark(x1))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(0, from(x1))) -> c5(A__FIRST(0, a__from(mark(x1))), MARK(0))
   MARK(first(nil, from(x1))) -> c5(A__FIRST(nil, a__from(mark(x1))), MARK(nil))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(cons(z0, z1), from(x1))) -> c5(A__FIRST(cons(mark(z0), z1), a__from(mark(x1))), MARK(cons(z0, z1)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), from(mark(x1))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(0, from(x1))) -> c5(A__FIRST(0, a__from(mark(x1))), MARK(0))
   MARK(first(nil, from(x1))) -> c5(A__FIRST(nil, a__from(mark(x1))), MARK(nil))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(cons(z0, z1), from(x1))) -> c5(A__FIRST(cons(mark(z0), z1), a__from(mark(x1))), MARK(cons(z0, z1)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_2, c5_1, c6_2, c6_1


----------------------------------------

(45) CdtLeafRemovalProof (BOTH BOUNDS(ID, ID))
Removed 2 trailing nodes:
   MARK(first(0, from(x1))) -> c5(A__FIRST(0, a__from(mark(x1))), MARK(0))
   MARK(first(nil, from(x1))) -> c5(A__FIRST(nil, a__from(mark(x1))), MARK(nil))

----------------------------------------

(46)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), from(mark(x1))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(cons(z0, z1), from(x1))) -> c5(A__FIRST(cons(mark(z0), z1), a__from(mark(x1))), MARK(cons(z0, z1)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), from(mark(x1))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(cons(z0, z1), from(x1))) -> c5(A__FIRST(cons(mark(z0), z1), a__from(mark(x1))), MARK(cons(z0, z1)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_2, c5_1, c6_2, c6_1


----------------------------------------

(47) CdtRhsSimplificationProcessorProof (BOTH BOUNDS(ID, ID))
Removed 2 trailing tuple parts
----------------------------------------

(48)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_2, c5_1, c6_2, c6_1


----------------------------------------

(49) CdtNarrowingProof (BOTH BOUNDS(ID, ID))
Use narrowing to replace MARK(first(x0, cons(z0, z1))) -> c5(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(x0)) by 
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(0, cons(x1, x2))) -> c5(A__FIRST(0, cons(mark(x1), x2)), MARK(0))
   MARK(first(nil, cons(x1, x2))) -> c5(A__FIRST(nil, cons(mark(x1), x2)), MARK(nil))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(A__FIRST(cons(mark(z0), z1), cons(mark(x1), x2)), MARK(cons(z0, z1)))

----------------------------------------

(50)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(0, cons(x1, x2))) -> c5(A__FIRST(0, cons(mark(x1), x2)), MARK(0))
   MARK(first(nil, cons(x1, x2))) -> c5(A__FIRST(nil, cons(mark(x1), x2)), MARK(nil))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(A__FIRST(cons(mark(z0), z1), cons(mark(x1), x2)), MARK(cons(z0, z1)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(0, cons(x1, x2))) -> c5(A__FIRST(0, cons(mark(x1), x2)), MARK(0))
   MARK(first(nil, cons(x1, x2))) -> c5(A__FIRST(nil, cons(mark(x1), x2)), MARK(nil))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(A__FIRST(cons(mark(z0), z1), cons(mark(x1), x2)), MARK(cons(z0, z1)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_2, c5_1, c6_2, c6_1


----------------------------------------

(51) CdtLeafRemovalProof (BOTH BOUNDS(ID, ID))
Removed 2 trailing nodes:
   MARK(first(0, cons(x1, x2))) -> c5(A__FIRST(0, cons(mark(x1), x2)), MARK(0))
   MARK(first(nil, cons(x1, x2))) -> c5(A__FIRST(nil, cons(mark(x1), x2)), MARK(nil))

----------------------------------------

(52)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(A__FIRST(cons(mark(z0), z1), cons(mark(x1), x2)), MARK(cons(z0, z1)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(A__FIRST(cons(mark(z0), z1), cons(mark(x1), x2)), MARK(cons(z0, z1)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_2, c5_1, c6_2, c6_1


----------------------------------------

(53) CdtRhsSimplificationProcessorProof (BOTH BOUNDS(ID, ID))
Removed 1 trailing tuple parts
----------------------------------------

(54)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1)))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_2, c5_1, c6_2, c6_1


----------------------------------------

(55) CdtNarrowingProof (BOTH BOUNDS(ID, ID))
Use narrowing to replace MARK(first(first(z0, z1), x1)) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(first(z0, z1))) by 
   MARK(first(first(x0, x1), first(z0, z1))) -> c5(A__FIRST(a__first(mark(x0), mark(x1)), a__first(mark(z0), mark(z1))), MARK(first(x0, x1)))
   MARK(first(first(x0, x1), from(z0))) -> c5(A__FIRST(a__first(mark(x0), mark(x1)), a__from(mark(z0))), MARK(first(x0, x1)))
   MARK(first(first(x0, x1), 0)) -> c5(A__FIRST(a__first(mark(x0), mark(x1)), 0), MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(A__FIRST(a__first(mark(x0), mark(x1)), nil), MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(A__FIRST(a__first(mark(x0), mark(x1)), s(mark(z0))), MARK(first(x0, x1)))
   MARK(first(first(x0, x1), cons(z0, z1))) -> c5(A__FIRST(a__first(mark(x0), mark(x1)), cons(mark(z0), z1)), MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(A__FIRST(first(mark(x0), mark(x1)), mark(x2)), MARK(first(x0, x1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))

----------------------------------------

(56)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, x1), 0)) -> c5(A__FIRST(a__first(mark(x0), mark(x1)), 0), MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(A__FIRST(a__first(mark(x0), mark(x1)), nil), MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(A__FIRST(a__first(mark(x0), mark(x1)), s(mark(z0))), MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(A__FIRST(first(mark(x0), mark(x1)), mark(x2)), MARK(first(x0, x1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, x1), 0)) -> c5(A__FIRST(a__first(mark(x0), mark(x1)), 0), MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(A__FIRST(a__first(mark(x0), mark(x1)), nil), MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(A__FIRST(a__first(mark(x0), mark(x1)), s(mark(z0))), MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(A__FIRST(first(mark(x0), mark(x1)), mark(x2)), MARK(first(x0, x1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_2, c5_1, c6_2, c6_1


----------------------------------------

(57) CdtRhsSimplificationProcessorProof (BOTH BOUNDS(ID, ID))
Removed 4 trailing tuple parts
----------------------------------------

(58)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0)))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_2, c5_1, c6_2, c6_1


----------------------------------------

(59) CdtNarrowingProof (BOTH BOUNDS(ID, ID))
Use narrowing to replace MARK(first(from(z0), x1)) -> c5(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(from(z0))) by 
   MARK(first(from(x0), first(z0, z1))) -> c5(A__FIRST(a__from(mark(x0)), a__first(mark(z0), mark(z1))), MARK(from(x0)))
   MARK(first(from(x0), from(z0))) -> c5(A__FIRST(a__from(mark(x0)), a__from(mark(z0))), MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(A__FIRST(a__from(mark(x0)), 0), MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(A__FIRST(a__from(mark(x0)), nil), MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(A__FIRST(a__from(mark(x0)), s(mark(z0))), MARK(from(x0)))
   MARK(first(from(x0), cons(z0, z1))) -> c5(A__FIRST(a__from(mark(x0)), cons(mark(z0), z1)), MARK(from(x0)))
   MARK(first(from(x0), x1)) -> c5(A__FIRST(cons(mark(mark(x0)), from(s(mark(x0)))), mark(x1)), MARK(from(x0)))
   MARK(first(from(x0), x1)) -> c5(A__FIRST(from(mark(x0)), mark(x1)), MARK(from(x0)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))

----------------------------------------

(60)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(x0), 0)) -> c5(A__FIRST(a__from(mark(x0)), 0), MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(A__FIRST(a__from(mark(x0)), nil), MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(A__FIRST(a__from(mark(x0)), s(mark(z0))), MARK(from(x0)))
   MARK(first(from(x0), x1)) -> c5(A__FIRST(cons(mark(mark(x0)), from(s(mark(x0)))), mark(x1)), MARK(from(x0)))
   MARK(first(from(x0), x1)) -> c5(A__FIRST(from(mark(x0)), mark(x1)), MARK(from(x0)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(x0), 0)) -> c5(A__FIRST(a__from(mark(x0)), 0), MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(A__FIRST(a__from(mark(x0)), nil), MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(A__FIRST(a__from(mark(x0)), s(mark(z0))), MARK(from(x0)))
   MARK(first(from(x0), x1)) -> c5(A__FIRST(cons(mark(mark(x0)), from(s(mark(x0)))), mark(x1)), MARK(from(x0)))
   MARK(first(from(x0), x1)) -> c5(A__FIRST(from(mark(x0)), mark(x1)), MARK(from(x0)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_2, c5_1, c6_2, c6_1


----------------------------------------

(61) CdtRhsSimplificationProcessorProof (BOTH BOUNDS(ID, ID))
Removed 5 trailing tuple parts
----------------------------------------

(62)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0)))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_2, c5_1, c6_2, c6_1


----------------------------------------

(63) CdtNarrowingProof (BOTH BOUNDS(ID, ID))
Use narrowing to replace MARK(first(s(z0), x1)) -> c5(A__FIRST(s(mark(z0)), mark(x1)), MARK(s(z0))) by 
   MARK(first(s(x0), first(z0, z1))) -> c5(A__FIRST(s(mark(x0)), a__first(mark(z0), mark(z1))), MARK(s(x0)))
   MARK(first(s(x0), from(z0))) -> c5(A__FIRST(s(mark(x0)), a__from(mark(z0))), MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(A__FIRST(s(mark(x0)), 0), MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(A__FIRST(s(mark(x0)), nil), MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(A__FIRST(s(mark(x0)), s(mark(z0))), MARK(s(x0)))
   MARK(first(s(x0), cons(z0, z1))) -> c5(A__FIRST(s(mark(x0)), cons(mark(z0), z1)), MARK(s(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))

----------------------------------------

(64)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(x0), 0)) -> c5(A__FIRST(s(mark(x0)), 0), MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(A__FIRST(s(mark(x0)), nil), MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(A__FIRST(s(mark(x0)), s(mark(z0))), MARK(s(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(x0), 0)) -> c5(A__FIRST(s(mark(x0)), 0), MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(A__FIRST(s(mark(x0)), nil), MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(A__FIRST(s(mark(x0)), s(mark(z0))), MARK(s(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_1, c6_2, c6_1, c5_2


----------------------------------------

(65) CdtRhsSimplificationProcessorProof (BOTH BOUNDS(ID, ID))
Removed 3 trailing tuple parts
----------------------------------------

(66)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_1, c6_2, c6_1, c5_2


----------------------------------------

(67) CdtNarrowingProof (BOTH BOUNDS(ID, ID))
Use narrowing to replace MARK(first(x0, first(z0, z1))) -> c6(A__FIRST(mark(x0), a__first(mark(z0), mark(z1))), MARK(first(z0, z1))) by 
   MARK(first(x0, first(x1, x2))) -> c6(A__FIRST(mark(x0), first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(A__FIRST(0, a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(A__FIRST(nil, a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(A__FIRST(cons(mark(z0), z1), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))

----------------------------------------

(68)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, x2))) -> c6(A__FIRST(mark(x0), first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(A__FIRST(0, a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(A__FIRST(nil, a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(A__FIRST(cons(mark(z0), z1), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, x2))) -> c6(A__FIRST(mark(x0), first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(A__FIRST(0, a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(A__FIRST(nil, a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(A__FIRST(cons(mark(z0), z1), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_1, c6_2, c6_1, c5_2


----------------------------------------

(69) CdtRhsSimplificationProcessorProof (BOTH BOUNDS(ID, ID))
Removed 4 trailing tuple parts
----------------------------------------

(70)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_1, c6_2, c6_1, c5_2


----------------------------------------

(71) CdtNarrowingProof (BOTH BOUNDS(ID, ID))
Use narrowing to replace MARK(first(x0, from(z0))) -> c6(A__FIRST(mark(x0), a__from(mark(z0))), MARK(from(z0))) by 
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(A__FIRST(0, a__from(mark(x1))), MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(A__FIRST(nil, a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(A__FIRST(cons(mark(z0), z1), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))

----------------------------------------

(72)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(A__FIRST(0, a__from(mark(x1))), MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(A__FIRST(nil, a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(A__FIRST(cons(mark(z0), z1), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(A__FIRST(0, a__from(mark(x1))), MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(A__FIRST(nil, a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(A__FIRST(cons(mark(z0), z1), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_1, c6_2, c6_1, c5_2


----------------------------------------

(73) CdtRhsSimplificationProcessorProof (BOTH BOUNDS(ID, ID))
Removed 4 trailing tuple parts
----------------------------------------

(74)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_1, c6_2, c6_1, c5_2


----------------------------------------

(75) CdtNarrowingProof (BOTH BOUNDS(ID, ID))
Use narrowing to replace MARK(first(x0, cons(z0, z1))) -> c6(A__FIRST(mark(x0), cons(mark(z0), z1)), MARK(cons(z0, z1))) by 
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(0, x2))) -> c6(A__FIRST(mark(x0), cons(0, x2)), MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(A__FIRST(mark(x0), cons(nil, x2)), MARK(cons(nil, x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(A__FIRST(0, cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(A__FIRST(nil, cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(A__FIRST(cons(mark(z0), z1), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))

----------------------------------------

(76)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(0, x2))) -> c6(A__FIRST(mark(x0), cons(0, x2)), MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(A__FIRST(mark(x0), cons(nil, x2)), MARK(cons(nil, x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(A__FIRST(0, cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(A__FIRST(nil, cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(A__FIRST(cons(mark(z0), z1), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(0, x2))) -> c6(A__FIRST(mark(x0), cons(0, x2)), MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(A__FIRST(mark(x0), cons(nil, x2)), MARK(cons(nil, x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(A__FIRST(0, cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(A__FIRST(nil, cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(A__FIRST(cons(mark(z0), z1), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_1, c6_2, c6_1, c5_2


----------------------------------------

(77) CdtRhsSimplificationProcessorProof (BOTH BOUNDS(ID, ID))
Removed 3 trailing tuple parts
----------------------------------------

(78)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(0, x2))) -> c6(A__FIRST(mark(x0), cons(0, x2)), MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(A__FIRST(mark(x0), cons(nil, x2)), MARK(cons(nil, x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(0, x2))) -> c6(A__FIRST(mark(x0), cons(0, x2)), MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(A__FIRST(mark(x0), cons(nil, x2)), MARK(cons(nil, x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_1, c6_2, c6_1, c5_2


----------------------------------------

(79) CdtNarrowingProof (BOTH BOUNDS(ID, ID))
Use narrowing to replace MARK(first(first(z0, z1), x1)) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), mark(x1)), MARK(x1)) by 
   MARK(first(first(x0, x1), first(z0, z1))) -> c6(A__FIRST(a__first(mark(x0), mark(x1)), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(first(x0, x1), from(z0))) -> c6(A__FIRST(a__first(mark(x0), mark(x1)), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(first(x0, x1), 0)) -> c6(A__FIRST(a__first(mark(x0), mark(x1)), 0), MARK(0))
   MARK(first(first(x0, x1), nil)) -> c6(A__FIRST(a__first(mark(x0), mark(x1)), nil), MARK(nil))
   MARK(first(first(x0, x1), s(z0))) -> c6(A__FIRST(a__first(mark(x0), mark(x1)), s(mark(z0))), MARK(s(z0)))
   MARK(first(first(x0, x1), cons(z0, z1))) -> c6(A__FIRST(a__first(mark(x0), mark(x1)), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(first(x0, x1), x2)) -> c6(A__FIRST(first(mark(x0), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))

----------------------------------------

(80)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(0, x2))) -> c6(A__FIRST(mark(x0), cons(0, x2)), MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(A__FIRST(mark(x0), cons(nil, x2)), MARK(cons(nil, x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(first(x0, x1), 0)) -> c6(A__FIRST(a__first(mark(x0), mark(x1)), 0), MARK(0))
   MARK(first(first(x0, x1), nil)) -> c6(A__FIRST(a__first(mark(x0), mark(x1)), nil), MARK(nil))
   MARK(first(first(x0, x1), s(z0))) -> c6(A__FIRST(a__first(mark(x0), mark(x1)), s(mark(z0))), MARK(s(z0)))
   MARK(first(first(x0, x1), x2)) -> c6(A__FIRST(first(mark(x0), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(0, x2))) -> c6(A__FIRST(mark(x0), cons(0, x2)), MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(A__FIRST(mark(x0), cons(nil, x2)), MARK(cons(nil, x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(first(x0, x1), 0)) -> c6(A__FIRST(a__first(mark(x0), mark(x1)), 0), MARK(0))
   MARK(first(first(x0, x1), nil)) -> c6(A__FIRST(a__first(mark(x0), mark(x1)), nil), MARK(nil))
   MARK(first(first(x0, x1), s(z0))) -> c6(A__FIRST(a__first(mark(x0), mark(x1)), s(mark(z0))), MARK(s(z0)))
   MARK(first(first(x0, x1), x2)) -> c6(A__FIRST(first(mark(x0), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_1, c6_2, c6_1, c5_2


----------------------------------------

(81) CdtLeafRemovalProof (BOTH BOUNDS(ID, ID))
Removed 2 trailing nodes:
   MARK(first(first(x0, x1), 0)) -> c6(A__FIRST(a__first(mark(x0), mark(x1)), 0), MARK(0))
   MARK(first(first(x0, x1), nil)) -> c6(A__FIRST(a__first(mark(x0), mark(x1)), nil), MARK(nil))

----------------------------------------

(82)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(0, x2))) -> c6(A__FIRST(mark(x0), cons(0, x2)), MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(A__FIRST(mark(x0), cons(nil, x2)), MARK(cons(nil, x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(first(x0, x1), s(z0))) -> c6(A__FIRST(a__first(mark(x0), mark(x1)), s(mark(z0))), MARK(s(z0)))
   MARK(first(first(x0, x1), x2)) -> c6(A__FIRST(first(mark(x0), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(0, x2))) -> c6(A__FIRST(mark(x0), cons(0, x2)), MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(A__FIRST(mark(x0), cons(nil, x2)), MARK(cons(nil, x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(first(x0, x1), s(z0))) -> c6(A__FIRST(a__first(mark(x0), mark(x1)), s(mark(z0))), MARK(s(z0)))
   MARK(first(first(x0, x1), x2)) -> c6(A__FIRST(first(mark(x0), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_1, c6_2, c6_1, c5_2


----------------------------------------

(83) CdtRhsSimplificationProcessorProof (BOTH BOUNDS(ID, ID))
Removed 2 trailing tuple parts
----------------------------------------

(84)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(0, x2))) -> c6(A__FIRST(mark(x0), cons(0, x2)), MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(A__FIRST(mark(x0), cons(nil, x2)), MARK(cons(nil, x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, x1), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(first(x0, x1), x2)) -> c6(MARK(x2))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(0, x2))) -> c6(A__FIRST(mark(x0), cons(0, x2)), MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(A__FIRST(mark(x0), cons(nil, x2)), MARK(cons(nil, x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, x1), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(first(x0, x1), x2)) -> c6(MARK(x2))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_1, c6_2, c6_1, c5_2


----------------------------------------

(85) CdtNarrowingProof (BOTH BOUNDS(ID, ID))
Use narrowing to replace MARK(first(from(z0), x1)) -> c6(A__FIRST(a__from(mark(z0)), mark(x1)), MARK(x1)) by 
   MARK(first(from(x0), first(z0, z1))) -> c6(A__FIRST(a__from(mark(x0)), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(from(x0), from(z0))) -> c6(A__FIRST(a__from(mark(x0)), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(from(x0), 0)) -> c6(A__FIRST(a__from(mark(x0)), 0), MARK(0))
   MARK(first(from(x0), nil)) -> c6(A__FIRST(a__from(mark(x0)), nil), MARK(nil))
   MARK(first(from(x0), s(z0))) -> c6(A__FIRST(a__from(mark(x0)), s(mark(z0))), MARK(s(z0)))
   MARK(first(from(x0), cons(z0, z1))) -> c6(A__FIRST(a__from(mark(x0)), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(from(x0), x1)) -> c6(A__FIRST(cons(mark(mark(x0)), from(s(mark(x0)))), mark(x1)), MARK(x1))
   MARK(first(from(x0), x1)) -> c6(A__FIRST(from(mark(x0)), mark(x1)), MARK(x1))
   MARK(first(from(first(z0, z1)), x1)) -> c6(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(from(from(z0)), x1)) -> c6(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(0), x1)) -> c6(A__FIRST(a__from(0), mark(x1)), MARK(x1))
   MARK(first(from(nil), x1)) -> c6(A__FIRST(a__from(nil), mark(x1)), MARK(x1))
   MARK(first(from(s(z0)), x1)) -> c6(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(cons(z0, z1)), x1)) -> c6(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(x1))

----------------------------------------

(86)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(0, x2))) -> c6(A__FIRST(mark(x0), cons(0, x2)), MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(A__FIRST(mark(x0), cons(nil, x2)), MARK(cons(nil, x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, x1), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(first(x0, x1), x2)) -> c6(MARK(x2))
   MARK(first(from(x0), 0)) -> c6(A__FIRST(a__from(mark(x0)), 0), MARK(0))
   MARK(first(from(x0), nil)) -> c6(A__FIRST(a__from(mark(x0)), nil), MARK(nil))
   MARK(first(from(x0), s(z0))) -> c6(A__FIRST(a__from(mark(x0)), s(mark(z0))), MARK(s(z0)))
   MARK(first(from(x0), x1)) -> c6(A__FIRST(cons(mark(mark(x0)), from(s(mark(x0)))), mark(x1)), MARK(x1))
   MARK(first(from(x0), x1)) -> c6(A__FIRST(from(mark(x0)), mark(x1)), MARK(x1))
   MARK(first(from(first(z0, z1)), x1)) -> c6(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(from(from(z0)), x1)) -> c6(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(0), x1)) -> c6(A__FIRST(a__from(0), mark(x1)), MARK(x1))
   MARK(first(from(nil), x1)) -> c6(A__FIRST(a__from(nil), mark(x1)), MARK(x1))
   MARK(first(from(s(z0)), x1)) -> c6(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(cons(z0, z1)), x1)) -> c6(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(x1))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(0, x2))) -> c6(A__FIRST(mark(x0), cons(0, x2)), MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(A__FIRST(mark(x0), cons(nil, x2)), MARK(cons(nil, x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, x1), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(first(x0, x1), x2)) -> c6(MARK(x2))
   MARK(first(from(x0), 0)) -> c6(A__FIRST(a__from(mark(x0)), 0), MARK(0))
   MARK(first(from(x0), nil)) -> c6(A__FIRST(a__from(mark(x0)), nil), MARK(nil))
   MARK(first(from(x0), s(z0))) -> c6(A__FIRST(a__from(mark(x0)), s(mark(z0))), MARK(s(z0)))
   MARK(first(from(x0), x1)) -> c6(A__FIRST(cons(mark(mark(x0)), from(s(mark(x0)))), mark(x1)), MARK(x1))
   MARK(first(from(x0), x1)) -> c6(A__FIRST(from(mark(x0)), mark(x1)), MARK(x1))
   MARK(first(from(first(z0, z1)), x1)) -> c6(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(from(from(z0)), x1)) -> c6(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(0), x1)) -> c6(A__FIRST(a__from(0), mark(x1)), MARK(x1))
   MARK(first(from(nil), x1)) -> c6(A__FIRST(a__from(nil), mark(x1)), MARK(x1))
   MARK(first(from(s(z0)), x1)) -> c6(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(cons(z0, z1)), x1)) -> c6(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(x1))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_1, c6_2, c6_1, c5_2


----------------------------------------

(87) CdtLeafRemovalProof (BOTH BOUNDS(ID, ID))
Removed 2 trailing nodes:
   MARK(first(from(x0), nil)) -> c6(A__FIRST(a__from(mark(x0)), nil), MARK(nil))
   MARK(first(from(x0), 0)) -> c6(A__FIRST(a__from(mark(x0)), 0), MARK(0))

----------------------------------------

(88)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(0, x2))) -> c6(A__FIRST(mark(x0), cons(0, x2)), MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(A__FIRST(mark(x0), cons(nil, x2)), MARK(cons(nil, x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, x1), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(first(x0, x1), x2)) -> c6(MARK(x2))
   MARK(first(from(x0), s(z0))) -> c6(A__FIRST(a__from(mark(x0)), s(mark(z0))), MARK(s(z0)))
   MARK(first(from(x0), x1)) -> c6(A__FIRST(cons(mark(mark(x0)), from(s(mark(x0)))), mark(x1)), MARK(x1))
   MARK(first(from(x0), x1)) -> c6(A__FIRST(from(mark(x0)), mark(x1)), MARK(x1))
   MARK(first(from(first(z0, z1)), x1)) -> c6(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(from(from(z0)), x1)) -> c6(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(0), x1)) -> c6(A__FIRST(a__from(0), mark(x1)), MARK(x1))
   MARK(first(from(nil), x1)) -> c6(A__FIRST(a__from(nil), mark(x1)), MARK(x1))
   MARK(first(from(s(z0)), x1)) -> c6(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(cons(z0, z1)), x1)) -> c6(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(x1))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(0, x2))) -> c6(A__FIRST(mark(x0), cons(0, x2)), MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(A__FIRST(mark(x0), cons(nil, x2)), MARK(cons(nil, x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, x1), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(first(x0, x1), x2)) -> c6(MARK(x2))
   MARK(first(from(x0), s(z0))) -> c6(A__FIRST(a__from(mark(x0)), s(mark(z0))), MARK(s(z0)))
   MARK(first(from(x0), x1)) -> c6(A__FIRST(cons(mark(mark(x0)), from(s(mark(x0)))), mark(x1)), MARK(x1))
   MARK(first(from(x0), x1)) -> c6(A__FIRST(from(mark(x0)), mark(x1)), MARK(x1))
   MARK(first(from(first(z0, z1)), x1)) -> c6(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(from(from(z0)), x1)) -> c6(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(0), x1)) -> c6(A__FIRST(a__from(0), mark(x1)), MARK(x1))
   MARK(first(from(nil), x1)) -> c6(A__FIRST(a__from(nil), mark(x1)), MARK(x1))
   MARK(first(from(s(z0)), x1)) -> c6(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(cons(z0, z1)), x1)) -> c6(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(x1))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_1, c6_2, c6_1, c5_2


----------------------------------------

(89) CdtRhsSimplificationProcessorProof (BOTH BOUNDS(ID, ID))
Removed 3 trailing tuple parts
----------------------------------------

(90)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(0, x2))) -> c6(A__FIRST(mark(x0), cons(0, x2)), MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(A__FIRST(mark(x0), cons(nil, x2)), MARK(cons(nil, x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, x1), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(first(x0, x1), x2)) -> c6(MARK(x2))
   MARK(first(from(first(z0, z1)), x1)) -> c6(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(from(from(z0)), x1)) -> c6(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(0), x1)) -> c6(A__FIRST(a__from(0), mark(x1)), MARK(x1))
   MARK(first(from(nil), x1)) -> c6(A__FIRST(a__from(nil), mark(x1)), MARK(x1))
   MARK(first(from(s(z0)), x1)) -> c6(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(cons(z0, z1)), x1)) -> c6(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(x1))
   MARK(first(from(x0), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(from(x0), x1)) -> c6(MARK(x1))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(0, x2))) -> c6(A__FIRST(mark(x0), cons(0, x2)), MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(A__FIRST(mark(x0), cons(nil, x2)), MARK(cons(nil, x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, x1), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(first(x0, x1), x2)) -> c6(MARK(x2))
   MARK(first(from(first(z0, z1)), x1)) -> c6(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(from(from(z0)), x1)) -> c6(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(0), x1)) -> c6(A__FIRST(a__from(0), mark(x1)), MARK(x1))
   MARK(first(from(nil), x1)) -> c6(A__FIRST(a__from(nil), mark(x1)), MARK(x1))
   MARK(first(from(s(z0)), x1)) -> c6(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(cons(z0, z1)), x1)) -> c6(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(x1))
   MARK(first(from(x0), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(from(x0), x1)) -> c6(MARK(x1))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_1, c6_2, c6_1, c5_2


----------------------------------------

(91) CdtNarrowingProof (BOTH BOUNDS(ID, ID))
Use narrowing to replace MARK(first(s(z0), x1)) -> c6(A__FIRST(s(mark(z0)), mark(x1)), MARK(x1)) by 
   MARK(first(s(x0), first(z0, z1))) -> c6(A__FIRST(s(mark(x0)), a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(first(s(x0), from(z0))) -> c6(A__FIRST(s(mark(x0)), a__from(mark(z0))), MARK(from(z0)))
   MARK(first(s(x0), 0)) -> c6(A__FIRST(s(mark(x0)), 0), MARK(0))
   MARK(first(s(x0), nil)) -> c6(A__FIRST(s(mark(x0)), nil), MARK(nil))
   MARK(first(s(x0), s(z0))) -> c6(A__FIRST(s(mark(x0)), s(mark(z0))), MARK(s(z0)))
   MARK(first(s(x0), cons(z0, z1))) -> c6(A__FIRST(s(mark(x0)), cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(s(first(z0, z1)), x1)) -> c6(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(s(from(z0)), x1)) -> c6(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(0), x1)) -> c6(A__FIRST(s(0), mark(x1)), MARK(x1))
   MARK(first(s(nil), x1)) -> c6(A__FIRST(s(nil), mark(x1)), MARK(x1))
   MARK(first(s(s(z0)), x1)) -> c6(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(cons(z0, z1)), x1)) -> c6(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(x1))

----------------------------------------

(92)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(0, x2))) -> c6(A__FIRST(mark(x0), cons(0, x2)), MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(A__FIRST(mark(x0), cons(nil, x2)), MARK(cons(nil, x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, x1), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(first(x0, x1), x2)) -> c6(MARK(x2))
   MARK(first(from(first(z0, z1)), x1)) -> c6(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(from(from(z0)), x1)) -> c6(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(0), x1)) -> c6(A__FIRST(a__from(0), mark(x1)), MARK(x1))
   MARK(first(from(nil), x1)) -> c6(A__FIRST(a__from(nil), mark(x1)), MARK(x1))
   MARK(first(from(s(z0)), x1)) -> c6(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(cons(z0, z1)), x1)) -> c6(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(x1))
   MARK(first(from(x0), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(from(x0), x1)) -> c6(MARK(x1))
   MARK(first(s(x0), 0)) -> c6(A__FIRST(s(mark(x0)), 0), MARK(0))
   MARK(first(s(x0), nil)) -> c6(A__FIRST(s(mark(x0)), nil), MARK(nil))
   MARK(first(s(x0), s(z0))) -> c6(A__FIRST(s(mark(x0)), s(mark(z0))), MARK(s(z0)))
   MARK(first(s(first(z0, z1)), x1)) -> c6(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(s(from(z0)), x1)) -> c6(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(0), x1)) -> c6(A__FIRST(s(0), mark(x1)), MARK(x1))
   MARK(first(s(nil), x1)) -> c6(A__FIRST(s(nil), mark(x1)), MARK(x1))
   MARK(first(s(s(z0)), x1)) -> c6(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(cons(z0, z1)), x1)) -> c6(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(x1))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(0, x2))) -> c6(A__FIRST(mark(x0), cons(0, x2)), MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(A__FIRST(mark(x0), cons(nil, x2)), MARK(cons(nil, x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, x1), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(first(x0, x1), x2)) -> c6(MARK(x2))
   MARK(first(from(first(z0, z1)), x1)) -> c6(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(from(from(z0)), x1)) -> c6(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(0), x1)) -> c6(A__FIRST(a__from(0), mark(x1)), MARK(x1))
   MARK(first(from(nil), x1)) -> c6(A__FIRST(a__from(nil), mark(x1)), MARK(x1))
   MARK(first(from(s(z0)), x1)) -> c6(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(cons(z0, z1)), x1)) -> c6(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(x1))
   MARK(first(from(x0), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(from(x0), x1)) -> c6(MARK(x1))
   MARK(first(s(x0), 0)) -> c6(A__FIRST(s(mark(x0)), 0), MARK(0))
   MARK(first(s(x0), nil)) -> c6(A__FIRST(s(mark(x0)), nil), MARK(nil))
   MARK(first(s(x0), s(z0))) -> c6(A__FIRST(s(mark(x0)), s(mark(z0))), MARK(s(z0)))
   MARK(first(s(first(z0, z1)), x1)) -> c6(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(s(from(z0)), x1)) -> c6(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(0), x1)) -> c6(A__FIRST(s(0), mark(x1)), MARK(x1))
   MARK(first(s(nil), x1)) -> c6(A__FIRST(s(nil), mark(x1)), MARK(x1))
   MARK(first(s(s(z0)), x1)) -> c6(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(cons(z0, z1)), x1)) -> c6(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(x1))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_1, c6_1, c5_2, c6_2


----------------------------------------

(93) CdtLeafRemovalProof (BOTH BOUNDS(ID, ID))
Removed 2 trailing nodes:
   MARK(first(s(x0), 0)) -> c6(A__FIRST(s(mark(x0)), 0), MARK(0))
   MARK(first(s(x0), nil)) -> c6(A__FIRST(s(mark(x0)), nil), MARK(nil))

----------------------------------------

(94)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(0, x2))) -> c6(A__FIRST(mark(x0), cons(0, x2)), MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(A__FIRST(mark(x0), cons(nil, x2)), MARK(cons(nil, x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, x1), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(first(x0, x1), x2)) -> c6(MARK(x2))
   MARK(first(from(first(z0, z1)), x1)) -> c6(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(from(from(z0)), x1)) -> c6(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(0), x1)) -> c6(A__FIRST(a__from(0), mark(x1)), MARK(x1))
   MARK(first(from(nil), x1)) -> c6(A__FIRST(a__from(nil), mark(x1)), MARK(x1))
   MARK(first(from(s(z0)), x1)) -> c6(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(cons(z0, z1)), x1)) -> c6(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(x1))
   MARK(first(from(x0), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(from(x0), x1)) -> c6(MARK(x1))
   MARK(first(s(x0), s(z0))) -> c6(A__FIRST(s(mark(x0)), s(mark(z0))), MARK(s(z0)))
   MARK(first(s(first(z0, z1)), x1)) -> c6(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(s(from(z0)), x1)) -> c6(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(0), x1)) -> c6(A__FIRST(s(0), mark(x1)), MARK(x1))
   MARK(first(s(nil), x1)) -> c6(A__FIRST(s(nil), mark(x1)), MARK(x1))
   MARK(first(s(s(z0)), x1)) -> c6(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(cons(z0, z1)), x1)) -> c6(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(x1))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(0, x2))) -> c6(A__FIRST(mark(x0), cons(0, x2)), MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(A__FIRST(mark(x0), cons(nil, x2)), MARK(cons(nil, x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, x1), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(first(x0, x1), x2)) -> c6(MARK(x2))
   MARK(first(from(first(z0, z1)), x1)) -> c6(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(from(from(z0)), x1)) -> c6(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(0), x1)) -> c6(A__FIRST(a__from(0), mark(x1)), MARK(x1))
   MARK(first(from(nil), x1)) -> c6(A__FIRST(a__from(nil), mark(x1)), MARK(x1))
   MARK(first(from(s(z0)), x1)) -> c6(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(cons(z0, z1)), x1)) -> c6(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(x1))
   MARK(first(from(x0), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(from(x0), x1)) -> c6(MARK(x1))
   MARK(first(s(x0), s(z0))) -> c6(A__FIRST(s(mark(x0)), s(mark(z0))), MARK(s(z0)))
   MARK(first(s(first(z0, z1)), x1)) -> c6(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(s(from(z0)), x1)) -> c6(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(0), x1)) -> c6(A__FIRST(s(0), mark(x1)), MARK(x1))
   MARK(first(s(nil), x1)) -> c6(A__FIRST(s(nil), mark(x1)), MARK(x1))
   MARK(first(s(s(z0)), x1)) -> c6(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(cons(z0, z1)), x1)) -> c6(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(x1))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_1, c6_1, c5_2, c6_2


----------------------------------------

(95) CdtRhsSimplificationProcessorProof (BOTH BOUNDS(ID, ID))
Removed 1 trailing tuple parts
----------------------------------------

(96)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(0, x2))) -> c6(A__FIRST(mark(x0), cons(0, x2)), MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(A__FIRST(mark(x0), cons(nil, x2)), MARK(cons(nil, x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, x1), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(first(x0, x1), x2)) -> c6(MARK(x2))
   MARK(first(from(first(z0, z1)), x1)) -> c6(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(from(from(z0)), x1)) -> c6(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(0), x1)) -> c6(A__FIRST(a__from(0), mark(x1)), MARK(x1))
   MARK(first(from(nil), x1)) -> c6(A__FIRST(a__from(nil), mark(x1)), MARK(x1))
   MARK(first(from(s(z0)), x1)) -> c6(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(cons(z0, z1)), x1)) -> c6(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(x1))
   MARK(first(from(x0), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(from(x0), x1)) -> c6(MARK(x1))
   MARK(first(s(first(z0, z1)), x1)) -> c6(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(s(from(z0)), x1)) -> c6(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(0), x1)) -> c6(A__FIRST(s(0), mark(x1)), MARK(x1))
   MARK(first(s(nil), x1)) -> c6(A__FIRST(s(nil), mark(x1)), MARK(x1))
   MARK(first(s(s(z0)), x1)) -> c6(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(cons(z0, z1)), x1)) -> c6(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(x1))
   MARK(first(s(x0), s(z0))) -> c6(MARK(s(z0)))
S tuples:
   A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1))
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(0, x2))) -> c6(A__FIRST(mark(x0), cons(0, x2)), MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(A__FIRST(mark(x0), cons(nil, x2)), MARK(cons(nil, x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, x1), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(first(x0, x1), x2)) -> c6(MARK(x2))
   MARK(first(from(first(z0, z1)), x1)) -> c6(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(from(from(z0)), x1)) -> c6(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(0), x1)) -> c6(A__FIRST(a__from(0), mark(x1)), MARK(x1))
   MARK(first(from(nil), x1)) -> c6(A__FIRST(a__from(nil), mark(x1)), MARK(x1))
   MARK(first(from(s(z0)), x1)) -> c6(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(cons(z0, z1)), x1)) -> c6(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(x1))
   MARK(first(from(x0), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(from(x0), x1)) -> c6(MARK(x1))
   MARK(first(s(first(z0, z1)), x1)) -> c6(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(s(from(z0)), x1)) -> c6(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(0), x1)) -> c6(A__FIRST(s(0), mark(x1)), MARK(x1))
   MARK(first(s(nil), x1)) -> c6(A__FIRST(s(nil), mark(x1)), MARK(x1))
   MARK(first(s(s(z0)), x1)) -> c6(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(cons(z0, z1)), x1)) -> c6(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(x1))
   MARK(first(s(x0), s(z0))) -> c6(MARK(s(z0)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FIRST_2, A__FROM_1, MARK_1

Compound Symbols:   c1_1, c3_1, c7_2, c10_1, c11_1, c5_1, c6_1, c5_2, c6_2


----------------------------------------

(97) CdtForwardInstantiationProof (BOTH BOUNDS(ID, ID))
Use forward instantiation to replace A__FIRST(s(z0), cons(z1, z2)) -> c1(MARK(z1)) by 
   A__FIRST(s(z0), cons(from(y0), z2)) -> c1(MARK(from(y0)))
   A__FIRST(s(z0), cons(s(y0), z2)) -> c1(MARK(s(y0)))
   A__FIRST(s(z0), cons(cons(y0, y1), z2)) -> c1(MARK(cons(y0, y1)))
   A__FIRST(s(z0), cons(first(y0, 0), z2)) -> c1(MARK(first(y0, 0)))
   A__FIRST(s(z0), cons(first(y0, nil), z2)) -> c1(MARK(first(y0, nil)))
   A__FIRST(s(z0), cons(first(y0, s(y1)), z2)) -> c1(MARK(first(y0, s(y1))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), y2), z2)) -> c1(MARK(first(cons(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(0, y0), z2)) -> c1(MARK(first(0, y0)))
   A__FIRST(s(z0), cons(first(nil, y0), z2)) -> c1(MARK(first(nil, y0)))
   A__FIRST(s(z0), cons(first(y0, first(y1, first(y2, y3))), z2)) -> c1(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FIRST(s(z0), cons(first(y0, first(y1, from(y2))), z2)) -> c1(MARK(first(y0, first(y1, from(y2)))))
   A__FIRST(s(z0), cons(first(y0, first(y1, 0)), z2)) -> c1(MARK(first(y0, first(y1, 0))))
   A__FIRST(s(z0), cons(first(y0, first(y1, nil)), z2)) -> c1(MARK(first(y0, first(y1, nil))))
   A__FIRST(s(z0), cons(first(y0, first(y1, s(y2))), z2)) -> c1(MARK(first(y0, first(y1, s(y2)))))
   A__FIRST(s(z0), cons(first(y0, first(y1, cons(y2, y3))), z2)) -> c1(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FIRST(s(z0), cons(first(y0, first(first(y1, y2), y3)), z2)) -> c1(MARK(first(y0, first(first(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(y0, first(from(y1), y2)), z2)) -> c1(MARK(first(y0, first(from(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, first(0, y1)), z2)) -> c1(MARK(first(y0, first(0, y1))))
   A__FIRST(s(z0), cons(first(y0, first(nil, y1)), z2)) -> c1(MARK(first(y0, first(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, first(s(y1), y2)), z2)) -> c1(MARK(first(y0, first(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, first(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), first(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), first(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), first(y1, y2)), z2)) -> c1(MARK(first(from(y0), first(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), first(y1, y2)), z2)) -> c1(MARK(first(s(y0), first(y1, y2))))
   A__FIRST(s(z0), cons(first(y0, first(y1, y2)), z2)) -> c1(MARK(first(y0, first(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), first(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FIRST(s(z0), cons(first(y0, from(y1)), z2)) -> c1(MARK(first(y0, from(y1))))
   A__FIRST(s(z0), cons(first(y0, from(first(y1, y2))), z2)) -> c1(MARK(first(y0, from(first(y1, y2)))))
   A__FIRST(s(z0), cons(first(y0, from(from(y1))), z2)) -> c1(MARK(first(y0, from(from(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(0)), z2)) -> c1(MARK(first(y0, from(0))))
   A__FIRST(s(z0), cons(first(y0, from(nil)), z2)) -> c1(MARK(first(y0, from(nil))))
   A__FIRST(s(z0), cons(first(y0, from(s(y1))), z2)) -> c1(MARK(first(y0, from(s(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(cons(y1, y2))), z2)) -> c1(MARK(first(y0, from(cons(y1, y2)))))
   A__FIRST(s(z0), cons(first(first(y0, y1), from(y2)), z2)) -> c1(MARK(first(first(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(from(y0), from(y1)), z2)) -> c1(MARK(first(from(y0), from(y1))))
   A__FIRST(s(z0), cons(first(s(y0), from(y1)), z2)) -> c1(MARK(first(s(y0), from(y1))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), from(y2)), z2)) -> c1(MARK(first(cons(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(y0, cons(first(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(y0, cons(from(y1), y2)), z2)) -> c1(MARK(first(y0, cons(from(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(0, y1)), z2)) -> c1(MARK(first(y0, cons(0, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(nil, y1)), z2)) -> c1(MARK(first(y0, cons(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(s(y1), y2)), z2)) -> c1(MARK(first(y0, cons(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), cons(y1, y2)), z2)) -> c1(MARK(first(from(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), cons(y1, y2)), z2)) -> c1(MARK(first(s(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(first(y0, first(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(y0, from(y1)), y2), z2)) -> c1(MARK(first(first(y0, from(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, 0), y1), z2)) -> c1(MARK(first(first(y0, 0), y1)))
   A__FIRST(s(z0), cons(first(first(y0, nil), y1), z2)) -> c1(MARK(first(first(y0, nil), y1)))
   A__FIRST(s(z0), cons(first(first(y0, s(y1)), y2), z2)) -> c1(MARK(first(first(y0, s(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, cons(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(first(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(first(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(from(y0), y1), y2), z2)) -> c1(MARK(first(first(from(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(0, y0), y1), z2)) -> c1(MARK(first(first(0, y0), y1)))
   A__FIRST(s(z0), cons(first(first(nil, y0), y1), z2)) -> c1(MARK(first(first(nil, y0), y1)))
   A__FIRST(s(z0), cons(first(first(s(y0), y1), y2), z2)) -> c1(MARK(first(first(s(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(cons(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(y0, y1), 0), z2)) -> c1(MARK(first(first(y0, y1), 0)))
   A__FIRST(s(z0), cons(first(first(y0, y1), nil), z2)) -> c1(MARK(first(first(y0, y1), nil)))
   A__FIRST(s(z0), cons(first(first(y0, y1), s(y2)), z2)) -> c1(MARK(first(first(y0, y1), s(y2))))
   A__FIRST(s(z0), cons(first(first(y0, y1), y2), z2)) -> c1(MARK(first(first(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(from(first(y0, y1)), y2), z2)) -> c1(MARK(first(from(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(from(y0)), y1), z2)) -> c1(MARK(first(from(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(0), y0), z2)) -> c1(MARK(first(from(0), y0)))
   A__FIRST(s(z0), cons(first(from(nil), y0), z2)) -> c1(MARK(first(from(nil), y0)))
   A__FIRST(s(z0), cons(first(from(s(y0)), y1), z2)) -> c1(MARK(first(from(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(cons(y0, y1)), y2), z2)) -> c1(MARK(first(from(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(y0), y1), z2)) -> c1(MARK(first(from(y0), y1)))
   A__FIRST(s(z0), cons(first(from(y0), 0), z2)) -> c1(MARK(first(from(y0), 0)))
   A__FIRST(s(z0), cons(first(from(y0), nil), z2)) -> c1(MARK(first(from(y0), nil)))
   A__FIRST(s(z0), cons(first(from(y0), s(y1)), z2)) -> c1(MARK(first(from(y0), s(y1))))
   A__FIRST(s(z0), cons(first(s(first(y0, y1)), y2), z2)) -> c1(MARK(first(s(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(from(y0)), y1), z2)) -> c1(MARK(first(s(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(0), y0), z2)) -> c1(MARK(first(s(0), y0)))
   A__FIRST(s(z0), cons(first(s(nil), y0), z2)) -> c1(MARK(first(s(nil), y0)))
   A__FIRST(s(z0), cons(first(s(s(y0)), y1), z2)) -> c1(MARK(first(s(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(cons(y0, y1)), y2), z2)) -> c1(MARK(first(s(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(y0), y1), z2)) -> c1(MARK(first(s(y0), y1)))
   A__FIRST(s(z0), cons(first(s(y0), 0), z2)) -> c1(MARK(first(s(y0), 0)))
   A__FIRST(s(z0), cons(first(s(y0), nil), z2)) -> c1(MARK(first(s(y0), nil)))
   A__FIRST(s(z0), cons(first(s(y0), s(y1)), z2)) -> c1(MARK(first(s(y0), s(y1))))
   A__FIRST(s(z0), cons(first(0, first(y0, y1)), z2)) -> c1(MARK(first(0, first(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, first(y0, y1)), z2)) -> c1(MARK(first(nil, first(y0, y1))))
   A__FIRST(s(z0), cons(first(0, from(y0)), z2)) -> c1(MARK(first(0, from(y0))))
   A__FIRST(s(z0), cons(first(nil, from(y0)), z2)) -> c1(MARK(first(nil, from(y0))))
   A__FIRST(s(z0), cons(first(y0, cons(y1, y2)), z2)) -> c1(MARK(first(y0, cons(y1, y2))))
   A__FIRST(s(z0), cons(first(0, cons(y0, y1)), z2)) -> c1(MARK(first(0, cons(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, cons(y0, y1)), z2)) -> c1(MARK(first(nil, cons(y0, y1))))

----------------------------------------

(98)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c5(A__FIRST(mark(x0), cons(0, x2)), MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(A__FIRST(mark(x0), cons(nil, x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(0, x2))) -> c6(A__FIRST(mark(x0), cons(0, x2)), MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(A__FIRST(mark(x0), cons(nil, x2)), MARK(cons(nil, x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, x1), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(first(x0, x1), x2)) -> c6(MARK(x2))
   MARK(first(from(first(z0, z1)), x1)) -> c6(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(from(from(z0)), x1)) -> c6(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(0), x1)) -> c6(A__FIRST(a__from(0), mark(x1)), MARK(x1))
   MARK(first(from(nil), x1)) -> c6(A__FIRST(a__from(nil), mark(x1)), MARK(x1))
   MARK(first(from(s(z0)), x1)) -> c6(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(cons(z0, z1)), x1)) -> c6(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(x1))
   MARK(first(from(x0), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(from(x0), x1)) -> c6(MARK(x1))
   MARK(first(s(first(z0, z1)), x1)) -> c6(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(s(from(z0)), x1)) -> c6(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(0), x1)) -> c6(A__FIRST(s(0), mark(x1)), MARK(x1))
   MARK(first(s(nil), x1)) -> c6(A__FIRST(s(nil), mark(x1)), MARK(x1))
   MARK(first(s(s(z0)), x1)) -> c6(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(cons(z0, z1)), x1)) -> c6(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(x1))
   MARK(first(s(x0), s(z0))) -> c6(MARK(s(z0)))
   A__FIRST(s(z0), cons(from(y0), z2)) -> c1(MARK(from(y0)))
   A__FIRST(s(z0), cons(s(y0), z2)) -> c1(MARK(s(y0)))
   A__FIRST(s(z0), cons(cons(y0, y1), z2)) -> c1(MARK(cons(y0, y1)))
   A__FIRST(s(z0), cons(first(y0, 0), z2)) -> c1(MARK(first(y0, 0)))
   A__FIRST(s(z0), cons(first(y0, nil), z2)) -> c1(MARK(first(y0, nil)))
   A__FIRST(s(z0), cons(first(y0, s(y1)), z2)) -> c1(MARK(first(y0, s(y1))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), y2), z2)) -> c1(MARK(first(cons(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(0, y0), z2)) -> c1(MARK(first(0, y0)))
   A__FIRST(s(z0), cons(first(nil, y0), z2)) -> c1(MARK(first(nil, y0)))
   A__FIRST(s(z0), cons(first(y0, first(y1, first(y2, y3))), z2)) -> c1(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FIRST(s(z0), cons(first(y0, first(y1, from(y2))), z2)) -> c1(MARK(first(y0, first(y1, from(y2)))))
   A__FIRST(s(z0), cons(first(y0, first(y1, 0)), z2)) -> c1(MARK(first(y0, first(y1, 0))))
   A__FIRST(s(z0), cons(first(y0, first(y1, nil)), z2)) -> c1(MARK(first(y0, first(y1, nil))))
   A__FIRST(s(z0), cons(first(y0, first(y1, s(y2))), z2)) -> c1(MARK(first(y0, first(y1, s(y2)))))
   A__FIRST(s(z0), cons(first(y0, first(y1, cons(y2, y3))), z2)) -> c1(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FIRST(s(z0), cons(first(y0, first(first(y1, y2), y3)), z2)) -> c1(MARK(first(y0, first(first(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(y0, first(from(y1), y2)), z2)) -> c1(MARK(first(y0, first(from(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, first(0, y1)), z2)) -> c1(MARK(first(y0, first(0, y1))))
   A__FIRST(s(z0), cons(first(y0, first(nil, y1)), z2)) -> c1(MARK(first(y0, first(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, first(s(y1), y2)), z2)) -> c1(MARK(first(y0, first(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, first(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), first(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), first(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), first(y1, y2)), z2)) -> c1(MARK(first(from(y0), first(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), first(y1, y2)), z2)) -> c1(MARK(first(s(y0), first(y1, y2))))
   A__FIRST(s(z0), cons(first(y0, first(y1, y2)), z2)) -> c1(MARK(first(y0, first(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), first(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FIRST(s(z0), cons(first(y0, from(y1)), z2)) -> c1(MARK(first(y0, from(y1))))
   A__FIRST(s(z0), cons(first(y0, from(first(y1, y2))), z2)) -> c1(MARK(first(y0, from(first(y1, y2)))))
   A__FIRST(s(z0), cons(first(y0, from(from(y1))), z2)) -> c1(MARK(first(y0, from(from(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(0)), z2)) -> c1(MARK(first(y0, from(0))))
   A__FIRST(s(z0), cons(first(y0, from(nil)), z2)) -> c1(MARK(first(y0, from(nil))))
   A__FIRST(s(z0), cons(first(y0, from(s(y1))), z2)) -> c1(MARK(first(y0, from(s(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(cons(y1, y2))), z2)) -> c1(MARK(first(y0, from(cons(y1, y2)))))
   A__FIRST(s(z0), cons(first(first(y0, y1), from(y2)), z2)) -> c1(MARK(first(first(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(from(y0), from(y1)), z2)) -> c1(MARK(first(from(y0), from(y1))))
   A__FIRST(s(z0), cons(first(s(y0), from(y1)), z2)) -> c1(MARK(first(s(y0), from(y1))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), from(y2)), z2)) -> c1(MARK(first(cons(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(y0, cons(first(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(y0, cons(from(y1), y2)), z2)) -> c1(MARK(first(y0, cons(from(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(0, y1)), z2)) -> c1(MARK(first(y0, cons(0, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(nil, y1)), z2)) -> c1(MARK(first(y0, cons(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(s(y1), y2)), z2)) -> c1(MARK(first(y0, cons(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), cons(y1, y2)), z2)) -> c1(MARK(first(from(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), cons(y1, y2)), z2)) -> c1(MARK(first(s(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(first(y0, first(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(y0, from(y1)), y2), z2)) -> c1(MARK(first(first(y0, from(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, 0), y1), z2)) -> c1(MARK(first(first(y0, 0), y1)))
   A__FIRST(s(z0), cons(first(first(y0, nil), y1), z2)) -> c1(MARK(first(first(y0, nil), y1)))
   A__FIRST(s(z0), cons(first(first(y0, s(y1)), y2), z2)) -> c1(MARK(first(first(y0, s(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, cons(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(first(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(first(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(from(y0), y1), y2), z2)) -> c1(MARK(first(first(from(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(0, y0), y1), z2)) -> c1(MARK(first(first(0, y0), y1)))
   A__FIRST(s(z0), cons(first(first(nil, y0), y1), z2)) -> c1(MARK(first(first(nil, y0), y1)))
   A__FIRST(s(z0), cons(first(first(s(y0), y1), y2), z2)) -> c1(MARK(first(first(s(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(cons(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(y0, y1), 0), z2)) -> c1(MARK(first(first(y0, y1), 0)))
   A__FIRST(s(z0), cons(first(first(y0, y1), nil), z2)) -> c1(MARK(first(first(y0, y1), nil)))
   A__FIRST(s(z0), cons(first(first(y0, y1), s(y2)), z2)) -> c1(MARK(first(first(y0, y1), s(y2))))
   A__FIRST(s(z0), cons(first(first(y0, y1), y2), z2)) -> c1(MARK(first(first(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(from(first(y0, y1)), y2), z2)) -> c1(MARK(first(from(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(from(y0)), y1), z2)) -> c1(MARK(first(from(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(0), y0), z2)) -> c1(MARK(first(from(0), y0)))
   A__FIRST(s(z0), cons(first(from(nil), y0), z2)) -> c1(MARK(first(from(nil), y0)))
   A__FIRST(s(z0), cons(first(from(s(y0)), y1), z2)) -> c1(MARK(first(from(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(cons(y0, y1)), y2), z2)) -> c1(MARK(first(from(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(y0), y1), z2)) -> c1(MARK(first(from(y0), y1)))
   A__FIRST(s(z0), cons(first(from(y0), 0), z2)) -> c1(MARK(first(from(y0), 0)))
   A__FIRST(s(z0), cons(first(from(y0), nil), z2)) -> c1(MARK(first(from(y0), nil)))
   A__FIRST(s(z0), cons(first(from(y0), s(y1)), z2)) -> c1(MARK(first(from(y0), s(y1))))
   A__FIRST(s(z0), cons(first(s(first(y0, y1)), y2), z2)) -> c1(MARK(first(s(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(from(y0)), y1), z2)) -> c1(MARK(first(s(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(0), y0), z2)) -> c1(MARK(first(s(0), y0)))
   A__FIRST(s(z0), cons(first(s(nil), y0), z2)) -> c1(MARK(first(s(nil), y0)))
   A__FIRST(s(z0), cons(first(s(s(y0)), y1), z2)) -> c1(MARK(first(s(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(cons(y0, y1)), y2), z2)) -> c1(MARK(first(s(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(y0), y1), z2)) -> c1(MARK(first(s(y0), y1)))
   A__FIRST(s(z0), cons(first(s(y0), 0), z2)) -> c1(MARK(first(s(y0), 0)))
   A__FIRST(s(z0), cons(first(s(y0), nil), z2)) -> c1(MARK(first(s(y0), nil)))
   A__FIRST(s(z0), cons(first(s(y0), s(y1)), z2)) -> c1(MARK(first(s(y0), s(y1))))
   A__FIRST(s(z0), cons(first(0, first(y0, y1)), z2)) -> c1(MARK(first(0, first(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, first(y0, y1)), z2)) -> c1(MARK(first(nil, first(y0, y1))))
   A__FIRST(s(z0), cons(first(0, from(y0)), z2)) -> c1(MARK(first(0, from(y0))))
   A__FIRST(s(z0), cons(first(nil, from(y0)), z2)) -> c1(MARK(first(nil, from(y0))))
   A__FIRST(s(z0), cons(first(y0, cons(y1, y2)), z2)) -> c1(MARK(first(y0, cons(y1, y2))))
   A__FIRST(s(z0), cons(first(0, cons(y0, y1)), z2)) -> c1(MARK(first(0, cons(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, cons(y0, y1)), z2)) -> c1(MARK(first(nil, cons(y0, y1))))
S tuples:
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
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   A__FIRST(s(z0), cons(first(y0, first(first(y1, y2), y3)), z2)) -> c1(MARK(first(y0, first(first(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(y0, first(from(y1), y2)), z2)) -> c1(MARK(first(y0, first(from(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, first(0, y1)), z2)) -> c1(MARK(first(y0, first(0, y1))))
   A__FIRST(s(z0), cons(first(y0, first(nil, y1)), z2)) -> c1(MARK(first(y0, first(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, first(s(y1), y2)), z2)) -> c1(MARK(first(y0, first(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, first(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), first(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), first(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), first(y1, y2)), z2)) -> c1(MARK(first(from(y0), first(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), first(y1, y2)), z2)) -> c1(MARK(first(s(y0), first(y1, y2))))
   A__FIRST(s(z0), cons(first(y0, first(y1, y2)), z2)) -> c1(MARK(first(y0, first(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), first(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FIRST(s(z0), cons(first(y0, from(y1)), z2)) -> c1(MARK(first(y0, from(y1))))
   A__FIRST(s(z0), cons(first(y0, from(first(y1, y2))), z2)) -> c1(MARK(first(y0, from(first(y1, y2)))))
   A__FIRST(s(z0), cons(first(y0, from(from(y1))), z2)) -> c1(MARK(first(y0, from(from(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(0)), z2)) -> c1(MARK(first(y0, from(0))))
   A__FIRST(s(z0), cons(first(y0, from(nil)), z2)) -> c1(MARK(first(y0, from(nil))))
   A__FIRST(s(z0), cons(first(y0, from(s(y1))), z2)) -> c1(MARK(first(y0, from(s(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(cons(y1, y2))), z2)) -> c1(MARK(first(y0, from(cons(y1, y2)))))
   A__FIRST(s(z0), cons(first(first(y0, y1), from(y2)), z2)) -> c1(MARK(first(first(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(from(y0), from(y1)), z2)) -> c1(MARK(first(from(y0), from(y1))))
   A__FIRST(s(z0), cons(first(s(y0), from(y1)), z2)) -> c1(MARK(first(s(y0), from(y1))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), from(y2)), z2)) -> c1(MARK(first(cons(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(y0, cons(first(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(y0, cons(from(y1), y2)), z2)) -> c1(MARK(first(y0, cons(from(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(0, y1)), z2)) -> c1(MARK(first(y0, cons(0, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(nil, y1)), z2)) -> c1(MARK(first(y0, cons(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(s(y1), y2)), z2)) -> c1(MARK(first(y0, cons(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), cons(y1, y2)), z2)) -> c1(MARK(first(from(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), cons(y1, y2)), z2)) -> c1(MARK(first(s(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(first(y0, first(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(y0, from(y1)), y2), z2)) -> c1(MARK(first(first(y0, from(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, 0), y1), z2)) -> c1(MARK(first(first(y0, 0), y1)))
   A__FIRST(s(z0), cons(first(first(y0, nil), y1), z2)) -> c1(MARK(first(first(y0, nil), y1)))
   A__FIRST(s(z0), cons(first(first(y0, s(y1)), y2), z2)) -> c1(MARK(first(first(y0, s(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, cons(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(first(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(first(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(from(y0), y1), y2), z2)) -> c1(MARK(first(first(from(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(0, y0), y1), z2)) -> c1(MARK(first(first(0, y0), y1)))
   A__FIRST(s(z0), cons(first(first(nil, y0), y1), z2)) -> c1(MARK(first(first(nil, y0), y1)))
   A__FIRST(s(z0), cons(first(first(s(y0), y1), y2), z2)) -> c1(MARK(first(first(s(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(cons(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(y0, y1), 0), z2)) -> c1(MARK(first(first(y0, y1), 0)))
   A__FIRST(s(z0), cons(first(first(y0, y1), nil), z2)) -> c1(MARK(first(first(y0, y1), nil)))
   A__FIRST(s(z0), cons(first(first(y0, y1), s(y2)), z2)) -> c1(MARK(first(first(y0, y1), s(y2))))
   A__FIRST(s(z0), cons(first(first(y0, y1), y2), z2)) -> c1(MARK(first(first(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(from(first(y0, y1)), y2), z2)) -> c1(MARK(first(from(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(from(y0)), y1), z2)) -> c1(MARK(first(from(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(0), y0), z2)) -> c1(MARK(first(from(0), y0)))
   A__FIRST(s(z0), cons(first(from(nil), y0), z2)) -> c1(MARK(first(from(nil), y0)))
   A__FIRST(s(z0), cons(first(from(s(y0)), y1), z2)) -> c1(MARK(first(from(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(cons(y0, y1)), y2), z2)) -> c1(MARK(first(from(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(y0), y1), z2)) -> c1(MARK(first(from(y0), y1)))
   A__FIRST(s(z0), cons(first(from(y0), 0), z2)) -> c1(MARK(first(from(y0), 0)))
   A__FIRST(s(z0), cons(first(from(y0), nil), z2)) -> c1(MARK(first(from(y0), nil)))
   A__FIRST(s(z0), cons(first(from(y0), s(y1)), z2)) -> c1(MARK(first(from(y0), s(y1))))
   A__FIRST(s(z0), cons(first(s(first(y0, y1)), y2), z2)) -> c1(MARK(first(s(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(from(y0)), y1), z2)) -> c1(MARK(first(s(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(0), y0), z2)) -> c1(MARK(first(s(0), y0)))
   A__FIRST(s(z0), cons(first(s(nil), y0), z2)) -> c1(MARK(first(s(nil), y0)))
   A__FIRST(s(z0), cons(first(s(s(y0)), y1), z2)) -> c1(MARK(first(s(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(cons(y0, y1)), y2), z2)) -> c1(MARK(first(s(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(y0), y1), z2)) -> c1(MARK(first(s(y0), y1)))
   A__FIRST(s(z0), cons(first(s(y0), 0), z2)) -> c1(MARK(first(s(y0), 0)))
   A__FIRST(s(z0), cons(first(s(y0), nil), z2)) -> c1(MARK(first(s(y0), nil)))
   A__FIRST(s(z0), cons(first(s(y0), s(y1)), z2)) -> c1(MARK(first(s(y0), s(y1))))
   A__FIRST(s(z0), cons(first(0, first(y0, y1)), z2)) -> c1(MARK(first(0, first(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, first(y0, y1)), z2)) -> c1(MARK(first(nil, first(y0, y1))))
   A__FIRST(s(z0), cons(first(0, from(y0)), z2)) -> c1(MARK(first(0, from(y0))))
   A__FIRST(s(z0), cons(first(nil, from(y0)), z2)) -> c1(MARK(first(nil, from(y0))))
   A__FIRST(s(z0), cons(first(y0, cons(y1, y2)), z2)) -> c1(MARK(first(y0, cons(y1, y2))))
   A__FIRST(s(z0), cons(first(0, cons(y0, y1)), z2)) -> c1(MARK(first(0, cons(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, cons(y0, y1)), z2)) -> c1(MARK(first(nil, cons(y0, y1))))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FROM_1, MARK_1, A__FIRST_2

Compound Symbols:   c3_1, c7_2, c10_1, c11_1, c5_1, c6_1, c5_2, c6_2, c1_1


----------------------------------------

(99) CdtRhsSimplificationProcessorProof (BOTH BOUNDS(ID, ID))
Removed 4 trailing tuple parts
----------------------------------------

(100)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)), MARK(from(0)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)), MARK(from(nil)))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)), MARK(from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)), MARK(from(nil)))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, x1), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(first(x0, x1), x2)) -> c6(MARK(x2))
   MARK(first(from(first(z0, z1)), x1)) -> c6(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(from(from(z0)), x1)) -> c6(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(0), x1)) -> c6(A__FIRST(a__from(0), mark(x1)), MARK(x1))
   MARK(first(from(nil), x1)) -> c6(A__FIRST(a__from(nil), mark(x1)), MARK(x1))
   MARK(first(from(s(z0)), x1)) -> c6(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(cons(z0, z1)), x1)) -> c6(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(x1))
   MARK(first(from(x0), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(from(x0), x1)) -> c6(MARK(x1))
   MARK(first(s(first(z0, z1)), x1)) -> c6(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(s(from(z0)), x1)) -> c6(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(0), x1)) -> c6(A__FIRST(s(0), mark(x1)), MARK(x1))
   MARK(first(s(nil), x1)) -> c6(A__FIRST(s(nil), mark(x1)), MARK(x1))
   MARK(first(s(s(z0)), x1)) -> c6(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(cons(z0, z1)), x1)) -> c6(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(x1))
   MARK(first(s(x0), s(z0))) -> c6(MARK(s(z0)))
   A__FIRST(s(z0), cons(from(y0), z2)) -> c1(MARK(from(y0)))
   A__FIRST(s(z0), cons(s(y0), z2)) -> c1(MARK(s(y0)))
   A__FIRST(s(z0), cons(cons(y0, y1), z2)) -> c1(MARK(cons(y0, y1)))
   A__FIRST(s(z0), cons(first(y0, 0), z2)) -> c1(MARK(first(y0, 0)))
   A__FIRST(s(z0), cons(first(y0, nil), z2)) -> c1(MARK(first(y0, nil)))
   A__FIRST(s(z0), cons(first(y0, s(y1)), z2)) -> c1(MARK(first(y0, s(y1))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), y2), z2)) -> c1(MARK(first(cons(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(0, y0), z2)) -> c1(MARK(first(0, y0)))
   A__FIRST(s(z0), cons(first(nil, y0), z2)) -> c1(MARK(first(nil, y0)))
   A__FIRST(s(z0), cons(first(y0, first(y1, first(y2, y3))), z2)) -> c1(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FIRST(s(z0), cons(first(y0, first(y1, from(y2))), z2)) -> c1(MARK(first(y0, first(y1, from(y2)))))
   A__FIRST(s(z0), cons(first(y0, first(y1, 0)), z2)) -> c1(MARK(first(y0, first(y1, 0))))
   A__FIRST(s(z0), cons(first(y0, first(y1, nil)), z2)) -> c1(MARK(first(y0, first(y1, nil))))
   A__FIRST(s(z0), cons(first(y0, first(y1, s(y2))), z2)) -> c1(MARK(first(y0, first(y1, s(y2)))))
   A__FIRST(s(z0), cons(first(y0, first(y1, cons(y2, y3))), z2)) -> c1(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FIRST(s(z0), cons(first(y0, first(first(y1, y2), y3)), z2)) -> c1(MARK(first(y0, first(first(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(y0, first(from(y1), y2)), z2)) -> c1(MARK(first(y0, first(from(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, first(0, y1)), z2)) -> c1(MARK(first(y0, first(0, y1))))
   A__FIRST(s(z0), cons(first(y0, first(nil, y1)), z2)) -> c1(MARK(first(y0, first(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, first(s(y1), y2)), z2)) -> c1(MARK(first(y0, first(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, first(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), first(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), first(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), first(y1, y2)), z2)) -> c1(MARK(first(from(y0), first(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), first(y1, y2)), z2)) -> c1(MARK(first(s(y0), first(y1, y2))))
   A__FIRST(s(z0), cons(first(y0, first(y1, y2)), z2)) -> c1(MARK(first(y0, first(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), first(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FIRST(s(z0), cons(first(y0, from(y1)), z2)) -> c1(MARK(first(y0, from(y1))))
   A__FIRST(s(z0), cons(first(y0, from(first(y1, y2))), z2)) -> c1(MARK(first(y0, from(first(y1, y2)))))
   A__FIRST(s(z0), cons(first(y0, from(from(y1))), z2)) -> c1(MARK(first(y0, from(from(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(0)), z2)) -> c1(MARK(first(y0, from(0))))
   A__FIRST(s(z0), cons(first(y0, from(nil)), z2)) -> c1(MARK(first(y0, from(nil))))
   A__FIRST(s(z0), cons(first(y0, from(s(y1))), z2)) -> c1(MARK(first(y0, from(s(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(cons(y1, y2))), z2)) -> c1(MARK(first(y0, from(cons(y1, y2)))))
   A__FIRST(s(z0), cons(first(first(y0, y1), from(y2)), z2)) -> c1(MARK(first(first(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(from(y0), from(y1)), z2)) -> c1(MARK(first(from(y0), from(y1))))
   A__FIRST(s(z0), cons(first(s(y0), from(y1)), z2)) -> c1(MARK(first(s(y0), from(y1))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), from(y2)), z2)) -> c1(MARK(first(cons(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(y0, cons(first(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(y0, cons(from(y1), y2)), z2)) -> c1(MARK(first(y0, cons(from(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(0, y1)), z2)) -> c1(MARK(first(y0, cons(0, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(nil, y1)), z2)) -> c1(MARK(first(y0, cons(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(s(y1), y2)), z2)) -> c1(MARK(first(y0, cons(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), cons(y1, y2)), z2)) -> c1(MARK(first(from(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), cons(y1, y2)), z2)) -> c1(MARK(first(s(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(first(y0, first(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(y0, from(y1)), y2), z2)) -> c1(MARK(first(first(y0, from(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, 0), y1), z2)) -> c1(MARK(first(first(y0, 0), y1)))
   A__FIRST(s(z0), cons(first(first(y0, nil), y1), z2)) -> c1(MARK(first(first(y0, nil), y1)))
   A__FIRST(s(z0), cons(first(first(y0, s(y1)), y2), z2)) -> c1(MARK(first(first(y0, s(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, cons(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(first(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(first(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(from(y0), y1), y2), z2)) -> c1(MARK(first(first(from(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(0, y0), y1), z2)) -> c1(MARK(first(first(0, y0), y1)))
   A__FIRST(s(z0), cons(first(first(nil, y0), y1), z2)) -> c1(MARK(first(first(nil, y0), y1)))
   A__FIRST(s(z0), cons(first(first(s(y0), y1), y2), z2)) -> c1(MARK(first(first(s(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(cons(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(y0, y1), 0), z2)) -> c1(MARK(first(first(y0, y1), 0)))
   A__FIRST(s(z0), cons(first(first(y0, y1), nil), z2)) -> c1(MARK(first(first(y0, y1), nil)))
   A__FIRST(s(z0), cons(first(first(y0, y1), s(y2)), z2)) -> c1(MARK(first(first(y0, y1), s(y2))))
   A__FIRST(s(z0), cons(first(first(y0, y1), y2), z2)) -> c1(MARK(first(first(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(from(first(y0, y1)), y2), z2)) -> c1(MARK(first(from(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(from(y0)), y1), z2)) -> c1(MARK(first(from(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(0), y0), z2)) -> c1(MARK(first(from(0), y0)))
   A__FIRST(s(z0), cons(first(from(nil), y0), z2)) -> c1(MARK(first(from(nil), y0)))
   A__FIRST(s(z0), cons(first(from(s(y0)), y1), z2)) -> c1(MARK(first(from(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(cons(y0, y1)), y2), z2)) -> c1(MARK(first(from(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(y0), y1), z2)) -> c1(MARK(first(from(y0), y1)))
   A__FIRST(s(z0), cons(first(from(y0), 0), z2)) -> c1(MARK(first(from(y0), 0)))
   A__FIRST(s(z0), cons(first(from(y0), nil), z2)) -> c1(MARK(first(from(y0), nil)))
   A__FIRST(s(z0), cons(first(from(y0), s(y1)), z2)) -> c1(MARK(first(from(y0), s(y1))))
   A__FIRST(s(z0), cons(first(s(first(y0, y1)), y2), z2)) -> c1(MARK(first(s(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(from(y0)), y1), z2)) -> c1(MARK(first(s(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(0), y0), z2)) -> c1(MARK(first(s(0), y0)))
   A__FIRST(s(z0), cons(first(s(nil), y0), z2)) -> c1(MARK(first(s(nil), y0)))
   A__FIRST(s(z0), cons(first(s(s(y0)), y1), z2)) -> c1(MARK(first(s(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(cons(y0, y1)), y2), z2)) -> c1(MARK(first(s(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(y0), y1), z2)) -> c1(MARK(first(s(y0), y1)))
   A__FIRST(s(z0), cons(first(s(y0), 0), z2)) -> c1(MARK(first(s(y0), 0)))
   A__FIRST(s(z0), cons(first(s(y0), nil), z2)) -> c1(MARK(first(s(y0), nil)))
   A__FIRST(s(z0), cons(first(s(y0), s(y1)), z2)) -> c1(MARK(first(s(y0), s(y1))))
   A__FIRST(s(z0), cons(first(0, first(y0, y1)), z2)) -> c1(MARK(first(0, first(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, first(y0, y1)), z2)) -> c1(MARK(first(nil, first(y0, y1))))
   A__FIRST(s(z0), cons(first(0, from(y0)), z2)) -> c1(MARK(first(0, from(y0))))
   A__FIRST(s(z0), cons(first(nil, from(y0)), z2)) -> c1(MARK(first(nil, from(y0))))
   A__FIRST(s(z0), cons(first(y0, cons(y1, y2)), z2)) -> c1(MARK(first(y0, cons(y1, y2))))
   A__FIRST(s(z0), cons(first(0, cons(y0, y1)), z2)) -> c1(MARK(first(0, cons(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, cons(y0, y1)), z2)) -> c1(MARK(first(nil, cons(y0, y1))))
   MARK(first(x0, cons(0, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c6(MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(MARK(cons(nil, x2)))
S tuples:
   A__FROM(z0) -> c3(MARK(z0))
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
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   A__FIRST(s(z0), cons(first(y0, first(from(y1), y2)), z2)) -> c1(MARK(first(y0, first(from(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, first(0, y1)), z2)) -> c1(MARK(first(y0, first(0, y1))))
   A__FIRST(s(z0), cons(first(y0, first(nil, y1)), z2)) -> c1(MARK(first(y0, first(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, first(s(y1), y2)), z2)) -> c1(MARK(first(y0, first(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, first(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), first(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), first(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), first(y1, y2)), z2)) -> c1(MARK(first(from(y0), first(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), first(y1, y2)), z2)) -> c1(MARK(first(s(y0), first(y1, y2))))
   A__FIRST(s(z0), cons(first(y0, first(y1, y2)), z2)) -> c1(MARK(first(y0, first(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), first(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FIRST(s(z0), cons(first(y0, from(y1)), z2)) -> c1(MARK(first(y0, from(y1))))
   A__FIRST(s(z0), cons(first(y0, from(first(y1, y2))), z2)) -> c1(MARK(first(y0, from(first(y1, y2)))))
   A__FIRST(s(z0), cons(first(y0, from(from(y1))), z2)) -> c1(MARK(first(y0, from(from(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(0)), z2)) -> c1(MARK(first(y0, from(0))))
   A__FIRST(s(z0), cons(first(y0, from(nil)), z2)) -> c1(MARK(first(y0, from(nil))))
   A__FIRST(s(z0), cons(first(y0, from(s(y1))), z2)) -> c1(MARK(first(y0, from(s(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(cons(y1, y2))), z2)) -> c1(MARK(first(y0, from(cons(y1, y2)))))
   A__FIRST(s(z0), cons(first(first(y0, y1), from(y2)), z2)) -> c1(MARK(first(first(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(from(y0), from(y1)), z2)) -> c1(MARK(first(from(y0), from(y1))))
   A__FIRST(s(z0), cons(first(s(y0), from(y1)), z2)) -> c1(MARK(first(s(y0), from(y1))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), from(y2)), z2)) -> c1(MARK(first(cons(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(y0, cons(first(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(y0, cons(from(y1), y2)), z2)) -> c1(MARK(first(y0, cons(from(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(0, y1)), z2)) -> c1(MARK(first(y0, cons(0, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(nil, y1)), z2)) -> c1(MARK(first(y0, cons(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(s(y1), y2)), z2)) -> c1(MARK(first(y0, cons(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), cons(y1, y2)), z2)) -> c1(MARK(first(from(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), cons(y1, y2)), z2)) -> c1(MARK(first(s(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(first(y0, first(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(y0, from(y1)), y2), z2)) -> c1(MARK(first(first(y0, from(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, 0), y1), z2)) -> c1(MARK(first(first(y0, 0), y1)))
   A__FIRST(s(z0), cons(first(first(y0, nil), y1), z2)) -> c1(MARK(first(first(y0, nil), y1)))
   A__FIRST(s(z0), cons(first(first(y0, s(y1)), y2), z2)) -> c1(MARK(first(first(y0, s(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, cons(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(first(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(first(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(from(y0), y1), y2), z2)) -> c1(MARK(first(first(from(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(0, y0), y1), z2)) -> c1(MARK(first(first(0, y0), y1)))
   A__FIRST(s(z0), cons(first(first(nil, y0), y1), z2)) -> c1(MARK(first(first(nil, y0), y1)))
   A__FIRST(s(z0), cons(first(first(s(y0), y1), y2), z2)) -> c1(MARK(first(first(s(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(cons(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(y0, y1), 0), z2)) -> c1(MARK(first(first(y0, y1), 0)))
   A__FIRST(s(z0), cons(first(first(y0, y1), nil), z2)) -> c1(MARK(first(first(y0, y1), nil)))
   A__FIRST(s(z0), cons(first(first(y0, y1), s(y2)), z2)) -> c1(MARK(first(first(y0, y1), s(y2))))
   A__FIRST(s(z0), cons(first(first(y0, y1), y2), z2)) -> c1(MARK(first(first(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(from(first(y0, y1)), y2), z2)) -> c1(MARK(first(from(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(from(y0)), y1), z2)) -> c1(MARK(first(from(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(0), y0), z2)) -> c1(MARK(first(from(0), y0)))
   A__FIRST(s(z0), cons(first(from(nil), y0), z2)) -> c1(MARK(first(from(nil), y0)))
   A__FIRST(s(z0), cons(first(from(s(y0)), y1), z2)) -> c1(MARK(first(from(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(cons(y0, y1)), y2), z2)) -> c1(MARK(first(from(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(y0), y1), z2)) -> c1(MARK(first(from(y0), y1)))
   A__FIRST(s(z0), cons(first(from(y0), 0), z2)) -> c1(MARK(first(from(y0), 0)))
   A__FIRST(s(z0), cons(first(from(y0), nil), z2)) -> c1(MARK(first(from(y0), nil)))
   A__FIRST(s(z0), cons(first(from(y0), s(y1)), z2)) -> c1(MARK(first(from(y0), s(y1))))
   A__FIRST(s(z0), cons(first(s(first(y0, y1)), y2), z2)) -> c1(MARK(first(s(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(from(y0)), y1), z2)) -> c1(MARK(first(s(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(0), y0), z2)) -> c1(MARK(first(s(0), y0)))
   A__FIRST(s(z0), cons(first(s(nil), y0), z2)) -> c1(MARK(first(s(nil), y0)))
   A__FIRST(s(z0), cons(first(s(s(y0)), y1), z2)) -> c1(MARK(first(s(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(cons(y0, y1)), y2), z2)) -> c1(MARK(first(s(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(y0), y1), z2)) -> c1(MARK(first(s(y0), y1)))
   A__FIRST(s(z0), cons(first(s(y0), 0), z2)) -> c1(MARK(first(s(y0), 0)))
   A__FIRST(s(z0), cons(first(s(y0), nil), z2)) -> c1(MARK(first(s(y0), nil)))
   A__FIRST(s(z0), cons(first(s(y0), s(y1)), z2)) -> c1(MARK(first(s(y0), s(y1))))
   A__FIRST(s(z0), cons(first(0, first(y0, y1)), z2)) -> c1(MARK(first(0, first(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, first(y0, y1)), z2)) -> c1(MARK(first(nil, first(y0, y1))))
   A__FIRST(s(z0), cons(first(0, from(y0)), z2)) -> c1(MARK(first(0, from(y0))))
   A__FIRST(s(z0), cons(first(nil, from(y0)), z2)) -> c1(MARK(first(nil, from(y0))))
   A__FIRST(s(z0), cons(first(y0, cons(y1, y2)), z2)) -> c1(MARK(first(y0, cons(y1, y2))))
   A__FIRST(s(z0), cons(first(0, cons(y0, y1)), z2)) -> c1(MARK(first(0, cons(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, cons(y0, y1)), z2)) -> c1(MARK(first(nil, cons(y0, y1))))
   MARK(first(x0, cons(0, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c6(MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(MARK(cons(nil, x2)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   A__FROM_1, MARK_1, A__FIRST_2

Compound Symbols:   c3_1, c7_2, c10_1, c11_1, c5_1, c6_1, c5_2, c6_2, c1_1


----------------------------------------

(101) CdtForwardInstantiationProof (BOTH BOUNDS(ID, ID))
Use forward instantiation to replace A__FROM(z0) -> c3(MARK(z0)) by 
   A__FROM(from(y0)) -> c3(MARK(from(y0)))
   A__FROM(s(y0)) -> c3(MARK(s(y0)))
   A__FROM(cons(y0, y1)) -> c3(MARK(cons(y0, y1)))
   A__FROM(first(y0, 0)) -> c3(MARK(first(y0, 0)))
   A__FROM(first(y0, nil)) -> c3(MARK(first(y0, nil)))
   A__FROM(first(y0, s(y1))) -> c3(MARK(first(y0, s(y1))))
   A__FROM(first(cons(y0, y1), y2)) -> c3(MARK(first(cons(y0, y1), y2)))
   A__FROM(first(0, y0)) -> c3(MARK(first(0, y0)))
   A__FROM(first(nil, y0)) -> c3(MARK(first(nil, y0)))
   A__FROM(first(y0, first(y1, first(y2, y3)))) -> c3(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FROM(first(y0, first(y1, from(y2)))) -> c3(MARK(first(y0, first(y1, from(y2)))))
   A__FROM(first(y0, first(y1, 0))) -> c3(MARK(first(y0, first(y1, 0))))
   A__FROM(first(y0, first(y1, nil))) -> c3(MARK(first(y0, first(y1, nil))))
   A__FROM(first(y0, first(y1, s(y2)))) -> c3(MARK(first(y0, first(y1, s(y2)))))
   A__FROM(first(y0, first(y1, cons(y2, y3)))) -> c3(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FROM(first(y0, first(first(y1, y2), y3))) -> c3(MARK(first(y0, first(first(y1, y2), y3))))
   A__FROM(first(y0, first(from(y1), y2))) -> c3(MARK(first(y0, first(from(y1), y2))))
   A__FROM(first(y0, first(0, y1))) -> c3(MARK(first(y0, first(0, y1))))
   A__FROM(first(y0, first(nil, y1))) -> c3(MARK(first(y0, first(nil, y1))))
   A__FROM(first(y0, first(s(y1), y2))) -> c3(MARK(first(y0, first(s(y1), y2))))
   A__FROM(first(y0, first(cons(y1, y2), y3))) -> c3(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), first(y2, y3))) -> c3(MARK(first(first(y0, y1), first(y2, y3))))
   A__FROM(first(from(y0), first(y1, y2))) -> c3(MARK(first(from(y0), first(y1, y2))))
   A__FROM(first(s(y0), first(y1, y2))) -> c3(MARK(first(s(y0), first(y1, y2))))
   A__FROM(first(y0, first(y1, y2))) -> c3(MARK(first(y0, first(y1, y2))))
   A__FROM(first(cons(y0, y1), first(y2, y3))) -> c3(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FROM(first(y0, from(y1))) -> c3(MARK(first(y0, from(y1))))
   A__FROM(first(y0, from(first(y1, y2)))) -> c3(MARK(first(y0, from(first(y1, y2)))))
   A__FROM(first(y0, from(from(y1)))) -> c3(MARK(first(y0, from(from(y1)))))
   A__FROM(first(y0, from(0))) -> c3(MARK(first(y0, from(0))))
   A__FROM(first(y0, from(nil))) -> c3(MARK(first(y0, from(nil))))
   A__FROM(first(y0, from(s(y1)))) -> c3(MARK(first(y0, from(s(y1)))))
   A__FROM(first(y0, from(cons(y1, y2)))) -> c3(MARK(first(y0, from(cons(y1, y2)))))
   A__FROM(first(first(y0, y1), from(y2))) -> c3(MARK(first(first(y0, y1), from(y2))))
   A__FROM(first(from(y0), from(y1))) -> c3(MARK(first(from(y0), from(y1))))
   A__FROM(first(s(y0), from(y1))) -> c3(MARK(first(s(y0), from(y1))))
   A__FROM(first(cons(y0, y1), from(y2))) -> c3(MARK(first(cons(y0, y1), from(y2))))
   A__FROM(first(y0, cons(first(y1, y2), y3))) -> c3(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FROM(first(y0, cons(from(y1), y2))) -> c3(MARK(first(y0, cons(from(y1), y2))))
   A__FROM(first(y0, cons(s(y1), y2))) -> c3(MARK(first(y0, cons(s(y1), y2))))
   A__FROM(first(y0, cons(cons(y1, y2), y3))) -> c3(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), cons(y2, y3))) -> c3(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FROM(first(from(y0), cons(y1, y2))) -> c3(MARK(first(from(y0), cons(y1, y2))))
   A__FROM(first(s(y0), cons(y1, y2))) -> c3(MARK(first(s(y0), cons(y1, y2))))
   A__FROM(first(cons(y0, y1), cons(y2, y3))) -> c3(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FROM(first(first(y0, first(y1, y2)), y3)) -> c3(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FROM(first(first(y0, from(y1)), y2)) -> c3(MARK(first(first(y0, from(y1)), y2)))
   A__FROM(first(first(y0, 0), y1)) -> c3(MARK(first(first(y0, 0), y1)))
   A__FROM(first(first(y0, nil), y1)) -> c3(MARK(first(first(y0, nil), y1)))
   A__FROM(first(first(y0, s(y1)), y2)) -> c3(MARK(first(first(y0, s(y1)), y2)))
   A__FROM(first(first(y0, cons(y1, y2)), y3)) -> c3(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FROM(first(first(first(y0, y1), y2), y3)) -> c3(MARK(first(first(first(y0, y1), y2), y3)))
   A__FROM(first(first(from(y0), y1), y2)) -> c3(MARK(first(first(from(y0), y1), y2)))
   A__FROM(first(first(0, y0), y1)) -> c3(MARK(first(first(0, y0), y1)))
   A__FROM(first(first(nil, y0), y1)) -> c3(MARK(first(first(nil, y0), y1)))
   A__FROM(first(first(s(y0), y1), y2)) -> c3(MARK(first(first(s(y0), y1), y2)))
   A__FROM(first(first(cons(y0, y1), y2), y3)) -> c3(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FROM(first(first(y0, y1), 0)) -> c3(MARK(first(first(y0, y1), 0)))
   A__FROM(first(first(y0, y1), nil)) -> c3(MARK(first(first(y0, y1), nil)))
   A__FROM(first(first(y0, y1), s(y2))) -> c3(MARK(first(first(y0, y1), s(y2))))
   A__FROM(first(first(y0, y1), y2)) -> c3(MARK(first(first(y0, y1), y2)))
   A__FROM(first(from(first(y0, y1)), y2)) -> c3(MARK(first(from(first(y0, y1)), y2)))
   A__FROM(first(from(from(y0)), y1)) -> c3(MARK(first(from(from(y0)), y1)))
   A__FROM(first(from(0), y0)) -> c3(MARK(first(from(0), y0)))
   A__FROM(first(from(nil), y0)) -> c3(MARK(first(from(nil), y0)))
   A__FROM(first(from(s(y0)), y1)) -> c3(MARK(first(from(s(y0)), y1)))
   A__FROM(first(from(cons(y0, y1)), y2)) -> c3(MARK(first(from(cons(y0, y1)), y2)))
   A__FROM(first(from(y0), y1)) -> c3(MARK(first(from(y0), y1)))
   A__FROM(first(from(y0), 0)) -> c3(MARK(first(from(y0), 0)))
   A__FROM(first(from(y0), nil)) -> c3(MARK(first(from(y0), nil)))
   A__FROM(first(from(y0), s(y1))) -> c3(MARK(first(from(y0), s(y1))))
   A__FROM(first(s(first(y0, y1)), y2)) -> c3(MARK(first(s(first(y0, y1)), y2)))
   A__FROM(first(s(from(y0)), y1)) -> c3(MARK(first(s(from(y0)), y1)))
   A__FROM(first(s(0), y0)) -> c3(MARK(first(s(0), y0)))
   A__FROM(first(s(nil), y0)) -> c3(MARK(first(s(nil), y0)))
   A__FROM(first(s(s(y0)), y1)) -> c3(MARK(first(s(s(y0)), y1)))
   A__FROM(first(s(cons(y0, y1)), y2)) -> c3(MARK(first(s(cons(y0, y1)), y2)))
   A__FROM(first(s(y0), y1)) -> c3(MARK(first(s(y0), y1)))
   A__FROM(first(s(y0), 0)) -> c3(MARK(first(s(y0), 0)))
   A__FROM(first(s(y0), nil)) -> c3(MARK(first(s(y0), nil)))
   A__FROM(first(s(y0), s(y1))) -> c3(MARK(first(s(y0), s(y1))))
   A__FROM(first(0, first(y0, y1))) -> c3(MARK(first(0, first(y0, y1))))
   A__FROM(first(nil, first(y0, y1))) -> c3(MARK(first(nil, first(y0, y1))))
   A__FROM(first(0, from(y0))) -> c3(MARK(first(0, from(y0))))
   A__FROM(first(nil, from(y0))) -> c3(MARK(first(nil, from(y0))))
   A__FROM(first(y0, cons(y1, y2))) -> c3(MARK(first(y0, cons(y1, y2))))
   A__FROM(first(0, cons(y0, y1))) -> c3(MARK(first(0, cons(y0, y1))))
   A__FROM(first(nil, cons(y0, y1))) -> c3(MARK(first(nil, cons(y0, y1))))
   A__FROM(first(y0, cons(0, y1))) -> c3(MARK(first(y0, cons(0, y1))))
   A__FROM(first(y0, cons(nil, y1))) -> c3(MARK(first(y0, cons(nil, y1))))

----------------------------------------

(102)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
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   A__FIRST(s(z0), cons(first(from(y0), first(y1, y2)), z2)) -> c1(MARK(first(from(y0), first(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), first(y1, y2)), z2)) -> c1(MARK(first(s(y0), first(y1, y2))))
   A__FIRST(s(z0), cons(first(y0, first(y1, y2)), z2)) -> c1(MARK(first(y0, first(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), first(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FIRST(s(z0), cons(first(y0, from(y1)), z2)) -> c1(MARK(first(y0, from(y1))))
   A__FIRST(s(z0), cons(first(y0, from(first(y1, y2))), z2)) -> c1(MARK(first(y0, from(first(y1, y2)))))
   A__FIRST(s(z0), cons(first(y0, from(from(y1))), z2)) -> c1(MARK(first(y0, from(from(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(0)), z2)) -> c1(MARK(first(y0, from(0))))
   A__FIRST(s(z0), cons(first(y0, from(nil)), z2)) -> c1(MARK(first(y0, from(nil))))
   A__FIRST(s(z0), cons(first(y0, from(s(y1))), z2)) -> c1(MARK(first(y0, from(s(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(cons(y1, y2))), z2)) -> c1(MARK(first(y0, from(cons(y1, y2)))))
   A__FIRST(s(z0), cons(first(first(y0, y1), from(y2)), z2)) -> c1(MARK(first(first(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(from(y0), from(y1)), z2)) -> c1(MARK(first(from(y0), from(y1))))
   A__FIRST(s(z0), cons(first(s(y0), from(y1)), z2)) -> c1(MARK(first(s(y0), from(y1))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), from(y2)), z2)) -> c1(MARK(first(cons(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(y0, cons(first(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(y0, cons(from(y1), y2)), z2)) -> c1(MARK(first(y0, cons(from(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(0, y1)), z2)) -> c1(MARK(first(y0, cons(0, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(nil, y1)), z2)) -> c1(MARK(first(y0, cons(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(s(y1), y2)), z2)) -> c1(MARK(first(y0, cons(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), cons(y1, y2)), z2)) -> c1(MARK(first(from(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), cons(y1, y2)), z2)) -> c1(MARK(first(s(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(first(y0, first(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(y0, from(y1)), y2), z2)) -> c1(MARK(first(first(y0, from(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, 0), y1), z2)) -> c1(MARK(first(first(y0, 0), y1)))
   A__FIRST(s(z0), cons(first(first(y0, nil), y1), z2)) -> c1(MARK(first(first(y0, nil), y1)))
   A__FIRST(s(z0), cons(first(first(y0, s(y1)), y2), z2)) -> c1(MARK(first(first(y0, s(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, cons(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(first(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(first(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(from(y0), y1), y2), z2)) -> c1(MARK(first(first(from(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(0, y0), y1), z2)) -> c1(MARK(first(first(0, y0), y1)))
   A__FIRST(s(z0), cons(first(first(nil, y0), y1), z2)) -> c1(MARK(first(first(nil, y0), y1)))
   A__FIRST(s(z0), cons(first(first(s(y0), y1), y2), z2)) -> c1(MARK(first(first(s(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(cons(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(y0, y1), 0), z2)) -> c1(MARK(first(first(y0, y1), 0)))
   A__FIRST(s(z0), cons(first(first(y0, y1), nil), z2)) -> c1(MARK(first(first(y0, y1), nil)))
   A__FIRST(s(z0), cons(first(first(y0, y1), s(y2)), z2)) -> c1(MARK(first(first(y0, y1), s(y2))))
   A__FIRST(s(z0), cons(first(first(y0, y1), y2), z2)) -> c1(MARK(first(first(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(from(first(y0, y1)), y2), z2)) -> c1(MARK(first(from(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(from(y0)), y1), z2)) -> c1(MARK(first(from(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(0), y0), z2)) -> c1(MARK(first(from(0), y0)))
   A__FIRST(s(z0), cons(first(from(nil), y0), z2)) -> c1(MARK(first(from(nil), y0)))
   A__FIRST(s(z0), cons(first(from(s(y0)), y1), z2)) -> c1(MARK(first(from(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(cons(y0, y1)), y2), z2)) -> c1(MARK(first(from(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(y0), y1), z2)) -> c1(MARK(first(from(y0), y1)))
   A__FIRST(s(z0), cons(first(from(y0), 0), z2)) -> c1(MARK(first(from(y0), 0)))
   A__FIRST(s(z0), cons(first(from(y0), nil), z2)) -> c1(MARK(first(from(y0), nil)))
   A__FIRST(s(z0), cons(first(from(y0), s(y1)), z2)) -> c1(MARK(first(from(y0), s(y1))))
   A__FIRST(s(z0), cons(first(s(first(y0, y1)), y2), z2)) -> c1(MARK(first(s(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(from(y0)), y1), z2)) -> c1(MARK(first(s(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(0), y0), z2)) -> c1(MARK(first(s(0), y0)))
   A__FIRST(s(z0), cons(first(s(nil), y0), z2)) -> c1(MARK(first(s(nil), y0)))
   A__FIRST(s(z0), cons(first(s(s(y0)), y1), z2)) -> c1(MARK(first(s(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(cons(y0, y1)), y2), z2)) -> c1(MARK(first(s(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(y0), y1), z2)) -> c1(MARK(first(s(y0), y1)))
   A__FIRST(s(z0), cons(first(s(y0), 0), z2)) -> c1(MARK(first(s(y0), 0)))
   A__FIRST(s(z0), cons(first(s(y0), nil), z2)) -> c1(MARK(first(s(y0), nil)))
   A__FIRST(s(z0), cons(first(s(y0), s(y1)), z2)) -> c1(MARK(first(s(y0), s(y1))))
   A__FIRST(s(z0), cons(first(0, first(y0, y1)), z2)) -> c1(MARK(first(0, first(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, first(y0, y1)), z2)) -> c1(MARK(first(nil, first(y0, y1))))
   A__FIRST(s(z0), cons(first(0, from(y0)), z2)) -> c1(MARK(first(0, from(y0))))
   A__FIRST(s(z0), cons(first(nil, from(y0)), z2)) -> c1(MARK(first(nil, from(y0))))
   A__FIRST(s(z0), cons(first(y0, cons(y1, y2)), z2)) -> c1(MARK(first(y0, cons(y1, y2))))
   A__FIRST(s(z0), cons(first(0, cons(y0, y1)), z2)) -> c1(MARK(first(0, cons(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, cons(y0, y1)), z2)) -> c1(MARK(first(nil, cons(y0, y1))))
   MARK(first(x0, cons(0, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c6(MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(MARK(cons(nil, x2)))
   A__FROM(from(y0)) -> c3(MARK(from(y0)))
   A__FROM(s(y0)) -> c3(MARK(s(y0)))
   A__FROM(cons(y0, y1)) -> c3(MARK(cons(y0, y1)))
   A__FROM(first(y0, 0)) -> c3(MARK(first(y0, 0)))
   A__FROM(first(y0, nil)) -> c3(MARK(first(y0, nil)))
   A__FROM(first(y0, s(y1))) -> c3(MARK(first(y0, s(y1))))
   A__FROM(first(cons(y0, y1), y2)) -> c3(MARK(first(cons(y0, y1), y2)))
   A__FROM(first(0, y0)) -> c3(MARK(first(0, y0)))
   A__FROM(first(nil, y0)) -> c3(MARK(first(nil, y0)))
   A__FROM(first(y0, first(y1, first(y2, y3)))) -> c3(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FROM(first(y0, first(y1, from(y2)))) -> c3(MARK(first(y0, first(y1, from(y2)))))
   A__FROM(first(y0, first(y1, 0))) -> c3(MARK(first(y0, first(y1, 0))))
   A__FROM(first(y0, first(y1, nil))) -> c3(MARK(first(y0, first(y1, nil))))
   A__FROM(first(y0, first(y1, s(y2)))) -> c3(MARK(first(y0, first(y1, s(y2)))))
   A__FROM(first(y0, first(y1, cons(y2, y3)))) -> c3(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FROM(first(y0, first(first(y1, y2), y3))) -> c3(MARK(first(y0, first(first(y1, y2), y3))))
   A__FROM(first(y0, first(from(y1), y2))) -> c3(MARK(first(y0, first(from(y1), y2))))
   A__FROM(first(y0, first(0, y1))) -> c3(MARK(first(y0, first(0, y1))))
   A__FROM(first(y0, first(nil, y1))) -> c3(MARK(first(y0, first(nil, y1))))
   A__FROM(first(y0, first(s(y1), y2))) -> c3(MARK(first(y0, first(s(y1), y2))))
   A__FROM(first(y0, first(cons(y1, y2), y3))) -> c3(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), first(y2, y3))) -> c3(MARK(first(first(y0, y1), first(y2, y3))))
   A__FROM(first(from(y0), first(y1, y2))) -> c3(MARK(first(from(y0), first(y1, y2))))
   A__FROM(first(s(y0), first(y1, y2))) -> c3(MARK(first(s(y0), first(y1, y2))))
   A__FROM(first(y0, first(y1, y2))) -> c3(MARK(first(y0, first(y1, y2))))
   A__FROM(first(cons(y0, y1), first(y2, y3))) -> c3(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FROM(first(y0, from(y1))) -> c3(MARK(first(y0, from(y1))))
   A__FROM(first(y0, from(first(y1, y2)))) -> c3(MARK(first(y0, from(first(y1, y2)))))
   A__FROM(first(y0, from(from(y1)))) -> c3(MARK(first(y0, from(from(y1)))))
   A__FROM(first(y0, from(0))) -> c3(MARK(first(y0, from(0))))
   A__FROM(first(y0, from(nil))) -> c3(MARK(first(y0, from(nil))))
   A__FROM(first(y0, from(s(y1)))) -> c3(MARK(first(y0, from(s(y1)))))
   A__FROM(first(y0, from(cons(y1, y2)))) -> c3(MARK(first(y0, from(cons(y1, y2)))))
   A__FROM(first(first(y0, y1), from(y2))) -> c3(MARK(first(first(y0, y1), from(y2))))
   A__FROM(first(from(y0), from(y1))) -> c3(MARK(first(from(y0), from(y1))))
   A__FROM(first(s(y0), from(y1))) -> c3(MARK(first(s(y0), from(y1))))
   A__FROM(first(cons(y0, y1), from(y2))) -> c3(MARK(first(cons(y0, y1), from(y2))))
   A__FROM(first(y0, cons(first(y1, y2), y3))) -> c3(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FROM(first(y0, cons(from(y1), y2))) -> c3(MARK(first(y0, cons(from(y1), y2))))
   A__FROM(first(y0, cons(s(y1), y2))) -> c3(MARK(first(y0, cons(s(y1), y2))))
   A__FROM(first(y0, cons(cons(y1, y2), y3))) -> c3(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), cons(y2, y3))) -> c3(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FROM(first(from(y0), cons(y1, y2))) -> c3(MARK(first(from(y0), cons(y1, y2))))
   A__FROM(first(s(y0), cons(y1, y2))) -> c3(MARK(first(s(y0), cons(y1, y2))))
   A__FROM(first(cons(y0, y1), cons(y2, y3))) -> c3(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FROM(first(first(y0, first(y1, y2)), y3)) -> c3(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FROM(first(first(y0, from(y1)), y2)) -> c3(MARK(first(first(y0, from(y1)), y2)))
   A__FROM(first(first(y0, 0), y1)) -> c3(MARK(first(first(y0, 0), y1)))
   A__FROM(first(first(y0, nil), y1)) -> c3(MARK(first(first(y0, nil), y1)))
   A__FROM(first(first(y0, s(y1)), y2)) -> c3(MARK(first(first(y0, s(y1)), y2)))
   A__FROM(first(first(y0, cons(y1, y2)), y3)) -> c3(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FROM(first(first(first(y0, y1), y2), y3)) -> c3(MARK(first(first(first(y0, y1), y2), y3)))
   A__FROM(first(first(from(y0), y1), y2)) -> c3(MARK(first(first(from(y0), y1), y2)))
   A__FROM(first(first(0, y0), y1)) -> c3(MARK(first(first(0, y0), y1)))
   A__FROM(first(first(nil, y0), y1)) -> c3(MARK(first(first(nil, y0), y1)))
   A__FROM(first(first(s(y0), y1), y2)) -> c3(MARK(first(first(s(y0), y1), y2)))
   A__FROM(first(first(cons(y0, y1), y2), y3)) -> c3(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FROM(first(first(y0, y1), 0)) -> c3(MARK(first(first(y0, y1), 0)))
   A__FROM(first(first(y0, y1), nil)) -> c3(MARK(first(first(y0, y1), nil)))
   A__FROM(first(first(y0, y1), s(y2))) -> c3(MARK(first(first(y0, y1), s(y2))))
   A__FROM(first(first(y0, y1), y2)) -> c3(MARK(first(first(y0, y1), y2)))
   A__FROM(first(from(first(y0, y1)), y2)) -> c3(MARK(first(from(first(y0, y1)), y2)))
   A__FROM(first(from(from(y0)), y1)) -> c3(MARK(first(from(from(y0)), y1)))
   A__FROM(first(from(0), y0)) -> c3(MARK(first(from(0), y0)))
   A__FROM(first(from(nil), y0)) -> c3(MARK(first(from(nil), y0)))
   A__FROM(first(from(s(y0)), y1)) -> c3(MARK(first(from(s(y0)), y1)))
   A__FROM(first(from(cons(y0, y1)), y2)) -> c3(MARK(first(from(cons(y0, y1)), y2)))
   A__FROM(first(from(y0), y1)) -> c3(MARK(first(from(y0), y1)))
   A__FROM(first(from(y0), 0)) -> c3(MARK(first(from(y0), 0)))
   A__FROM(first(from(y0), nil)) -> c3(MARK(first(from(y0), nil)))
   A__FROM(first(from(y0), s(y1))) -> c3(MARK(first(from(y0), s(y1))))
   A__FROM(first(s(first(y0, y1)), y2)) -> c3(MARK(first(s(first(y0, y1)), y2)))
   A__FROM(first(s(from(y0)), y1)) -> c3(MARK(first(s(from(y0)), y1)))
   A__FROM(first(s(0), y0)) -> c3(MARK(first(s(0), y0)))
   A__FROM(first(s(nil), y0)) -> c3(MARK(first(s(nil), y0)))
   A__FROM(first(s(s(y0)), y1)) -> c3(MARK(first(s(s(y0)), y1)))
   A__FROM(first(s(cons(y0, y1)), y2)) -> c3(MARK(first(s(cons(y0, y1)), y2)))
   A__FROM(first(s(y0), y1)) -> c3(MARK(first(s(y0), y1)))
   A__FROM(first(s(y0), 0)) -> c3(MARK(first(s(y0), 0)))
   A__FROM(first(s(y0), nil)) -> c3(MARK(first(s(y0), nil)))
   A__FROM(first(s(y0), s(y1))) -> c3(MARK(first(s(y0), s(y1))))
   A__FROM(first(0, first(y0, y1))) -> c3(MARK(first(0, first(y0, y1))))
   A__FROM(first(nil, first(y0, y1))) -> c3(MARK(first(nil, first(y0, y1))))
   A__FROM(first(0, from(y0))) -> c3(MARK(first(0, from(y0))))
   A__FROM(first(nil, from(y0))) -> c3(MARK(first(nil, from(y0))))
   A__FROM(first(y0, cons(y1, y2))) -> c3(MARK(first(y0, cons(y1, y2))))
   A__FROM(first(0, cons(y0, y1))) -> c3(MARK(first(0, cons(y0, y1))))
   A__FROM(first(nil, cons(y0, y1))) -> c3(MARK(first(nil, cons(y0, y1))))
   A__FROM(first(y0, cons(0, y1))) -> c3(MARK(first(y0, cons(0, y1))))
   A__FROM(first(y0, cons(nil, y1))) -> c3(MARK(first(y0, cons(nil, y1))))
S tuples:
   MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0))
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
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   A__FIRST(s(z0), cons(first(cons(y0, y1), from(y2)), z2)) -> c1(MARK(first(cons(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(y0, cons(first(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(y0, cons(from(y1), y2)), z2)) -> c1(MARK(first(y0, cons(from(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(0, y1)), z2)) -> c1(MARK(first(y0, cons(0, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(nil, y1)), z2)) -> c1(MARK(first(y0, cons(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(s(y1), y2)), z2)) -> c1(MARK(first(y0, cons(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), cons(y1, y2)), z2)) -> c1(MARK(first(from(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), cons(y1, y2)), z2)) -> c1(MARK(first(s(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(first(y0, first(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(y0, from(y1)), y2), z2)) -> c1(MARK(first(first(y0, from(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, 0), y1), z2)) -> c1(MARK(first(first(y0, 0), y1)))
   A__FIRST(s(z0), cons(first(first(y0, nil), y1), z2)) -> c1(MARK(first(first(y0, nil), y1)))
   A__FIRST(s(z0), cons(first(first(y0, s(y1)), y2), z2)) -> c1(MARK(first(first(y0, s(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, cons(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(first(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(first(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(from(y0), y1), y2), z2)) -> c1(MARK(first(first(from(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(0, y0), y1), z2)) -> c1(MARK(first(first(0, y0), y1)))
   A__FIRST(s(z0), cons(first(first(nil, y0), y1), z2)) -> c1(MARK(first(first(nil, y0), y1)))
   A__FIRST(s(z0), cons(first(first(s(y0), y1), y2), z2)) -> c1(MARK(first(first(s(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(cons(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(y0, y1), 0), z2)) -> c1(MARK(first(first(y0, y1), 0)))
   A__FIRST(s(z0), cons(first(first(y0, y1), nil), z2)) -> c1(MARK(first(first(y0, y1), nil)))
   A__FIRST(s(z0), cons(first(first(y0, y1), s(y2)), z2)) -> c1(MARK(first(first(y0, y1), s(y2))))
   A__FIRST(s(z0), cons(first(first(y0, y1), y2), z2)) -> c1(MARK(first(first(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(from(first(y0, y1)), y2), z2)) -> c1(MARK(first(from(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(from(y0)), y1), z2)) -> c1(MARK(first(from(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(0), y0), z2)) -> c1(MARK(first(from(0), y0)))
   A__FIRST(s(z0), cons(first(from(nil), y0), z2)) -> c1(MARK(first(from(nil), y0)))
   A__FIRST(s(z0), cons(first(from(s(y0)), y1), z2)) -> c1(MARK(first(from(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(cons(y0, y1)), y2), z2)) -> c1(MARK(first(from(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(y0), y1), z2)) -> c1(MARK(first(from(y0), y1)))
   A__FIRST(s(z0), cons(first(from(y0), 0), z2)) -> c1(MARK(first(from(y0), 0)))
   A__FIRST(s(z0), cons(first(from(y0), nil), z2)) -> c1(MARK(first(from(y0), nil)))
   A__FIRST(s(z0), cons(first(from(y0), s(y1)), z2)) -> c1(MARK(first(from(y0), s(y1))))
   A__FIRST(s(z0), cons(first(s(first(y0, y1)), y2), z2)) -> c1(MARK(first(s(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(from(y0)), y1), z2)) -> c1(MARK(first(s(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(0), y0), z2)) -> c1(MARK(first(s(0), y0)))
   A__FIRST(s(z0), cons(first(s(nil), y0), z2)) -> c1(MARK(first(s(nil), y0)))
   A__FIRST(s(z0), cons(first(s(s(y0)), y1), z2)) -> c1(MARK(first(s(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(cons(y0, y1)), y2), z2)) -> c1(MARK(first(s(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(y0), y1), z2)) -> c1(MARK(first(s(y0), y1)))
   A__FIRST(s(z0), cons(first(s(y0), 0), z2)) -> c1(MARK(first(s(y0), 0)))
   A__FIRST(s(z0), cons(first(s(y0), nil), z2)) -> c1(MARK(first(s(y0), nil)))
   A__FIRST(s(z0), cons(first(s(y0), s(y1)), z2)) -> c1(MARK(first(s(y0), s(y1))))
   A__FIRST(s(z0), cons(first(0, first(y0, y1)), z2)) -> c1(MARK(first(0, first(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, first(y0, y1)), z2)) -> c1(MARK(first(nil, first(y0, y1))))
   A__FIRST(s(z0), cons(first(0, from(y0)), z2)) -> c1(MARK(first(0, from(y0))))
   A__FIRST(s(z0), cons(first(nil, from(y0)), z2)) -> c1(MARK(first(nil, from(y0))))
   A__FIRST(s(z0), cons(first(y0, cons(y1, y2)), z2)) -> c1(MARK(first(y0, cons(y1, y2))))
   A__FIRST(s(z0), cons(first(0, cons(y0, y1)), z2)) -> c1(MARK(first(0, cons(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, cons(y0, y1)), z2)) -> c1(MARK(first(nil, cons(y0, y1))))
   MARK(first(x0, cons(0, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c6(MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(MARK(cons(nil, x2)))
   A__FROM(from(y0)) -> c3(MARK(from(y0)))
   A__FROM(s(y0)) -> c3(MARK(s(y0)))
   A__FROM(cons(y0, y1)) -> c3(MARK(cons(y0, y1)))
   A__FROM(first(y0, 0)) -> c3(MARK(first(y0, 0)))
   A__FROM(first(y0, nil)) -> c3(MARK(first(y0, nil)))
   A__FROM(first(y0, s(y1))) -> c3(MARK(first(y0, s(y1))))
   A__FROM(first(cons(y0, y1), y2)) -> c3(MARK(first(cons(y0, y1), y2)))
   A__FROM(first(0, y0)) -> c3(MARK(first(0, y0)))
   A__FROM(first(nil, y0)) -> c3(MARK(first(nil, y0)))
   A__FROM(first(y0, first(y1, first(y2, y3)))) -> c3(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FROM(first(y0, first(y1, from(y2)))) -> c3(MARK(first(y0, first(y1, from(y2)))))
   A__FROM(first(y0, first(y1, 0))) -> c3(MARK(first(y0, first(y1, 0))))
   A__FROM(first(y0, first(y1, nil))) -> c3(MARK(first(y0, first(y1, nil))))
   A__FROM(first(y0, first(y1, s(y2)))) -> c3(MARK(first(y0, first(y1, s(y2)))))
   A__FROM(first(y0, first(y1, cons(y2, y3)))) -> c3(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FROM(first(y0, first(first(y1, y2), y3))) -> c3(MARK(first(y0, first(first(y1, y2), y3))))
   A__FROM(first(y0, first(from(y1), y2))) -> c3(MARK(first(y0, first(from(y1), y2))))
   A__FROM(first(y0, first(0, y1))) -> c3(MARK(first(y0, first(0, y1))))
   A__FROM(first(y0, first(nil, y1))) -> c3(MARK(first(y0, first(nil, y1))))
   A__FROM(first(y0, first(s(y1), y2))) -> c3(MARK(first(y0, first(s(y1), y2))))
   A__FROM(first(y0, first(cons(y1, y2), y3))) -> c3(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), first(y2, y3))) -> c3(MARK(first(first(y0, y1), first(y2, y3))))
   A__FROM(first(from(y0), first(y1, y2))) -> c3(MARK(first(from(y0), first(y1, y2))))
   A__FROM(first(s(y0), first(y1, y2))) -> c3(MARK(first(s(y0), first(y1, y2))))
   A__FROM(first(y0, first(y1, y2))) -> c3(MARK(first(y0, first(y1, y2))))
   A__FROM(first(cons(y0, y1), first(y2, y3))) -> c3(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FROM(first(y0, from(y1))) -> c3(MARK(first(y0, from(y1))))
   A__FROM(first(y0, from(first(y1, y2)))) -> c3(MARK(first(y0, from(first(y1, y2)))))
   A__FROM(first(y0, from(from(y1)))) -> c3(MARK(first(y0, from(from(y1)))))
   A__FROM(first(y0, from(0))) -> c3(MARK(first(y0, from(0))))
   A__FROM(first(y0, from(nil))) -> c3(MARK(first(y0, from(nil))))
   A__FROM(first(y0, from(s(y1)))) -> c3(MARK(first(y0, from(s(y1)))))
   A__FROM(first(y0, from(cons(y1, y2)))) -> c3(MARK(first(y0, from(cons(y1, y2)))))
   A__FROM(first(first(y0, y1), from(y2))) -> c3(MARK(first(first(y0, y1), from(y2))))
   A__FROM(first(from(y0), from(y1))) -> c3(MARK(first(from(y0), from(y1))))
   A__FROM(first(s(y0), from(y1))) -> c3(MARK(first(s(y0), from(y1))))
   A__FROM(first(cons(y0, y1), from(y2))) -> c3(MARK(first(cons(y0, y1), from(y2))))
   A__FROM(first(y0, cons(first(y1, y2), y3))) -> c3(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FROM(first(y0, cons(from(y1), y2))) -> c3(MARK(first(y0, cons(from(y1), y2))))
   A__FROM(first(y0, cons(s(y1), y2))) -> c3(MARK(first(y0, cons(s(y1), y2))))
   A__FROM(first(y0, cons(cons(y1, y2), y3))) -> c3(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), cons(y2, y3))) -> c3(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FROM(first(from(y0), cons(y1, y2))) -> c3(MARK(first(from(y0), cons(y1, y2))))
   A__FROM(first(s(y0), cons(y1, y2))) -> c3(MARK(first(s(y0), cons(y1, y2))))
   A__FROM(first(cons(y0, y1), cons(y2, y3))) -> c3(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FROM(first(first(y0, first(y1, y2)), y3)) -> c3(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FROM(first(first(y0, from(y1)), y2)) -> c3(MARK(first(first(y0, from(y1)), y2)))
   A__FROM(first(first(y0, 0), y1)) -> c3(MARK(first(first(y0, 0), y1)))
   A__FROM(first(first(y0, nil), y1)) -> c3(MARK(first(first(y0, nil), y1)))
   A__FROM(first(first(y0, s(y1)), y2)) -> c3(MARK(first(first(y0, s(y1)), y2)))
   A__FROM(first(first(y0, cons(y1, y2)), y3)) -> c3(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FROM(first(first(first(y0, y1), y2), y3)) -> c3(MARK(first(first(first(y0, y1), y2), y3)))
   A__FROM(first(first(from(y0), y1), y2)) -> c3(MARK(first(first(from(y0), y1), y2)))
   A__FROM(first(first(0, y0), y1)) -> c3(MARK(first(first(0, y0), y1)))
   A__FROM(first(first(nil, y0), y1)) -> c3(MARK(first(first(nil, y0), y1)))
   A__FROM(first(first(s(y0), y1), y2)) -> c3(MARK(first(first(s(y0), y1), y2)))
   A__FROM(first(first(cons(y0, y1), y2), y3)) -> c3(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FROM(first(first(y0, y1), 0)) -> c3(MARK(first(first(y0, y1), 0)))
   A__FROM(first(first(y0, y1), nil)) -> c3(MARK(first(first(y0, y1), nil)))
   A__FROM(first(first(y0, y1), s(y2))) -> c3(MARK(first(first(y0, y1), s(y2))))
   A__FROM(first(first(y0, y1), y2)) -> c3(MARK(first(first(y0, y1), y2)))
   A__FROM(first(from(first(y0, y1)), y2)) -> c3(MARK(first(from(first(y0, y1)), y2)))
   A__FROM(first(from(from(y0)), y1)) -> c3(MARK(first(from(from(y0)), y1)))
   A__FROM(first(from(0), y0)) -> c3(MARK(first(from(0), y0)))
   A__FROM(first(from(nil), y0)) -> c3(MARK(first(from(nil), y0)))
   A__FROM(first(from(s(y0)), y1)) -> c3(MARK(first(from(s(y0)), y1)))
   A__FROM(first(from(cons(y0, y1)), y2)) -> c3(MARK(first(from(cons(y0, y1)), y2)))
   A__FROM(first(from(y0), y1)) -> c3(MARK(first(from(y0), y1)))
   A__FROM(first(from(y0), 0)) -> c3(MARK(first(from(y0), 0)))
   A__FROM(first(from(y0), nil)) -> c3(MARK(first(from(y0), nil)))
   A__FROM(first(from(y0), s(y1))) -> c3(MARK(first(from(y0), s(y1))))
   A__FROM(first(s(first(y0, y1)), y2)) -> c3(MARK(first(s(first(y0, y1)), y2)))
   A__FROM(first(s(from(y0)), y1)) -> c3(MARK(first(s(from(y0)), y1)))
   A__FROM(first(s(0), y0)) -> c3(MARK(first(s(0), y0)))
   A__FROM(first(s(nil), y0)) -> c3(MARK(first(s(nil), y0)))
   A__FROM(first(s(s(y0)), y1)) -> c3(MARK(first(s(s(y0)), y1)))
   A__FROM(first(s(cons(y0, y1)), y2)) -> c3(MARK(first(s(cons(y0, y1)), y2)))
   A__FROM(first(s(y0), y1)) -> c3(MARK(first(s(y0), y1)))
   A__FROM(first(s(y0), 0)) -> c3(MARK(first(s(y0), 0)))
   A__FROM(first(s(y0), nil)) -> c3(MARK(first(s(y0), nil)))
   A__FROM(first(s(y0), s(y1))) -> c3(MARK(first(s(y0), s(y1))))
   A__FROM(first(0, first(y0, y1))) -> c3(MARK(first(0, first(y0, y1))))
   A__FROM(first(nil, first(y0, y1))) -> c3(MARK(first(nil, first(y0, y1))))
   A__FROM(first(0, from(y0))) -> c3(MARK(first(0, from(y0))))
   A__FROM(first(nil, from(y0))) -> c3(MARK(first(nil, from(y0))))
   A__FROM(first(y0, cons(y1, y2))) -> c3(MARK(first(y0, cons(y1, y2))))
   A__FROM(first(0, cons(y0, y1))) -> c3(MARK(first(0, cons(y0, y1))))
   A__FROM(first(nil, cons(y0, y1))) -> c3(MARK(first(nil, cons(y0, y1))))
   A__FROM(first(y0, cons(0, y1))) -> c3(MARK(first(y0, cons(0, y1))))
   A__FROM(first(y0, cons(nil, y1))) -> c3(MARK(first(y0, cons(nil, y1))))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   MARK_1, A__FIRST_2, A__FROM_1

Compound Symbols:   c7_2, c10_1, c11_1, c5_1, c6_1, c5_2, c6_2, c1_1, c3_1


----------------------------------------

(103) CdtNarrowingProof (BOTH BOUNDS(ID, ID))
Use narrowing to replace MARK(from(z0)) -> c7(A__FROM(mark(z0)), MARK(z0)) by 
   MARK(from(first(z0, z1))) -> c7(A__FROM(a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(from(from(z0))) -> c7(A__FROM(a__from(mark(z0))), MARK(from(z0)))
   MARK(from(0)) -> c7(A__FROM(0), MARK(0))
   MARK(from(nil)) -> c7(A__FROM(nil), MARK(nil))
   MARK(from(s(z0))) -> c7(A__FROM(s(mark(z0))), MARK(s(z0)))
   MARK(from(cons(z0, z1))) -> c7(A__FROM(cons(mark(z0), z1)), MARK(cons(z0, z1)))

----------------------------------------

(104)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
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   A__FIRST(s(z0), cons(first(y0, cons(0, y1)), z2)) -> c1(MARK(first(y0, cons(0, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(nil, y1)), z2)) -> c1(MARK(first(y0, cons(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(s(y1), y2)), z2)) -> c1(MARK(first(y0, cons(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), cons(y1, y2)), z2)) -> c1(MARK(first(from(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), cons(y1, y2)), z2)) -> c1(MARK(first(s(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(first(y0, first(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(y0, from(y1)), y2), z2)) -> c1(MARK(first(first(y0, from(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, 0), y1), z2)) -> c1(MARK(first(first(y0, 0), y1)))
   A__FIRST(s(z0), cons(first(first(y0, nil), y1), z2)) -> c1(MARK(first(first(y0, nil), y1)))
   A__FIRST(s(z0), cons(first(first(y0, s(y1)), y2), z2)) -> c1(MARK(first(first(y0, s(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, cons(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(first(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(first(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(from(y0), y1), y2), z2)) -> c1(MARK(first(first(from(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(0, y0), y1), z2)) -> c1(MARK(first(first(0, y0), y1)))
   A__FIRST(s(z0), cons(first(first(nil, y0), y1), z2)) -> c1(MARK(first(first(nil, y0), y1)))
   A__FIRST(s(z0), cons(first(first(s(y0), y1), y2), z2)) -> c1(MARK(first(first(s(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(cons(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(y0, y1), 0), z2)) -> c1(MARK(first(first(y0, y1), 0)))
   A__FIRST(s(z0), cons(first(first(y0, y1), nil), z2)) -> c1(MARK(first(first(y0, y1), nil)))
   A__FIRST(s(z0), cons(first(first(y0, y1), s(y2)), z2)) -> c1(MARK(first(first(y0, y1), s(y2))))
   A__FIRST(s(z0), cons(first(first(y0, y1), y2), z2)) -> c1(MARK(first(first(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(from(first(y0, y1)), y2), z2)) -> c1(MARK(first(from(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(from(y0)), y1), z2)) -> c1(MARK(first(from(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(0), y0), z2)) -> c1(MARK(first(from(0), y0)))
   A__FIRST(s(z0), cons(first(from(nil), y0), z2)) -> c1(MARK(first(from(nil), y0)))
   A__FIRST(s(z0), cons(first(from(s(y0)), y1), z2)) -> c1(MARK(first(from(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(cons(y0, y1)), y2), z2)) -> c1(MARK(first(from(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(y0), y1), z2)) -> c1(MARK(first(from(y0), y1)))
   A__FIRST(s(z0), cons(first(from(y0), 0), z2)) -> c1(MARK(first(from(y0), 0)))
   A__FIRST(s(z0), cons(first(from(y0), nil), z2)) -> c1(MARK(first(from(y0), nil)))
   A__FIRST(s(z0), cons(first(from(y0), s(y1)), z2)) -> c1(MARK(first(from(y0), s(y1))))
   A__FIRST(s(z0), cons(first(s(first(y0, y1)), y2), z2)) -> c1(MARK(first(s(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(from(y0)), y1), z2)) -> c1(MARK(first(s(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(0), y0), z2)) -> c1(MARK(first(s(0), y0)))
   A__FIRST(s(z0), cons(first(s(nil), y0), z2)) -> c1(MARK(first(s(nil), y0)))
   A__FIRST(s(z0), cons(first(s(s(y0)), y1), z2)) -> c1(MARK(first(s(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(cons(y0, y1)), y2), z2)) -> c1(MARK(first(s(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(y0), y1), z2)) -> c1(MARK(first(s(y0), y1)))
   A__FIRST(s(z0), cons(first(s(y0), 0), z2)) -> c1(MARK(first(s(y0), 0)))
   A__FIRST(s(z0), cons(first(s(y0), nil), z2)) -> c1(MARK(first(s(y0), nil)))
   A__FIRST(s(z0), cons(first(s(y0), s(y1)), z2)) -> c1(MARK(first(s(y0), s(y1))))
   A__FIRST(s(z0), cons(first(0, first(y0, y1)), z2)) -> c1(MARK(first(0, first(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, first(y0, y1)), z2)) -> c1(MARK(first(nil, first(y0, y1))))
   A__FIRST(s(z0), cons(first(0, from(y0)), z2)) -> c1(MARK(first(0, from(y0))))
   A__FIRST(s(z0), cons(first(nil, from(y0)), z2)) -> c1(MARK(first(nil, from(y0))))
   A__FIRST(s(z0), cons(first(y0, cons(y1, y2)), z2)) -> c1(MARK(first(y0, cons(y1, y2))))
   A__FIRST(s(z0), cons(first(0, cons(y0, y1)), z2)) -> c1(MARK(first(0, cons(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, cons(y0, y1)), z2)) -> c1(MARK(first(nil, cons(y0, y1))))
   MARK(first(x0, cons(0, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c6(MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(MARK(cons(nil, x2)))
   A__FROM(from(y0)) -> c3(MARK(from(y0)))
   A__FROM(s(y0)) -> c3(MARK(s(y0)))
   A__FROM(cons(y0, y1)) -> c3(MARK(cons(y0, y1)))
   A__FROM(first(y0, 0)) -> c3(MARK(first(y0, 0)))
   A__FROM(first(y0, nil)) -> c3(MARK(first(y0, nil)))
   A__FROM(first(y0, s(y1))) -> c3(MARK(first(y0, s(y1))))
   A__FROM(first(cons(y0, y1), y2)) -> c3(MARK(first(cons(y0, y1), y2)))
   A__FROM(first(0, y0)) -> c3(MARK(first(0, y0)))
   A__FROM(first(nil, y0)) -> c3(MARK(first(nil, y0)))
   A__FROM(first(y0, first(y1, first(y2, y3)))) -> c3(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FROM(first(y0, first(y1, from(y2)))) -> c3(MARK(first(y0, first(y1, from(y2)))))
   A__FROM(first(y0, first(y1, 0))) -> c3(MARK(first(y0, first(y1, 0))))
   A__FROM(first(y0, first(y1, nil))) -> c3(MARK(first(y0, first(y1, nil))))
   A__FROM(first(y0, first(y1, s(y2)))) -> c3(MARK(first(y0, first(y1, s(y2)))))
   A__FROM(first(y0, first(y1, cons(y2, y3)))) -> c3(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FROM(first(y0, first(first(y1, y2), y3))) -> c3(MARK(first(y0, first(first(y1, y2), y3))))
   A__FROM(first(y0, first(from(y1), y2))) -> c3(MARK(first(y0, first(from(y1), y2))))
   A__FROM(first(y0, first(0, y1))) -> c3(MARK(first(y0, first(0, y1))))
   A__FROM(first(y0, first(nil, y1))) -> c3(MARK(first(y0, first(nil, y1))))
   A__FROM(first(y0, first(s(y1), y2))) -> c3(MARK(first(y0, first(s(y1), y2))))
   A__FROM(first(y0, first(cons(y1, y2), y3))) -> c3(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), first(y2, y3))) -> c3(MARK(first(first(y0, y1), first(y2, y3))))
   A__FROM(first(from(y0), first(y1, y2))) -> c3(MARK(first(from(y0), first(y1, y2))))
   A__FROM(first(s(y0), first(y1, y2))) -> c3(MARK(first(s(y0), first(y1, y2))))
   A__FROM(first(y0, first(y1, y2))) -> c3(MARK(first(y0, first(y1, y2))))
   A__FROM(first(cons(y0, y1), first(y2, y3))) -> c3(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FROM(first(y0, from(y1))) -> c3(MARK(first(y0, from(y1))))
   A__FROM(first(y0, from(first(y1, y2)))) -> c3(MARK(first(y0, from(first(y1, y2)))))
   A__FROM(first(y0, from(from(y1)))) -> c3(MARK(first(y0, from(from(y1)))))
   A__FROM(first(y0, from(0))) -> c3(MARK(first(y0, from(0))))
   A__FROM(first(y0, from(nil))) -> c3(MARK(first(y0, from(nil))))
   A__FROM(first(y0, from(s(y1)))) -> c3(MARK(first(y0, from(s(y1)))))
   A__FROM(first(y0, from(cons(y1, y2)))) -> c3(MARK(first(y0, from(cons(y1, y2)))))
   A__FROM(first(first(y0, y1), from(y2))) -> c3(MARK(first(first(y0, y1), from(y2))))
   A__FROM(first(from(y0), from(y1))) -> c3(MARK(first(from(y0), from(y1))))
   A__FROM(first(s(y0), from(y1))) -> c3(MARK(first(s(y0), from(y1))))
   A__FROM(first(cons(y0, y1), from(y2))) -> c3(MARK(first(cons(y0, y1), from(y2))))
   A__FROM(first(y0, cons(first(y1, y2), y3))) -> c3(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FROM(first(y0, cons(from(y1), y2))) -> c3(MARK(first(y0, cons(from(y1), y2))))
   A__FROM(first(y0, cons(s(y1), y2))) -> c3(MARK(first(y0, cons(s(y1), y2))))
   A__FROM(first(y0, cons(cons(y1, y2), y3))) -> c3(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), cons(y2, y3))) -> c3(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FROM(first(from(y0), cons(y1, y2))) -> c3(MARK(first(from(y0), cons(y1, y2))))
   A__FROM(first(s(y0), cons(y1, y2))) -> c3(MARK(first(s(y0), cons(y1, y2))))
   A__FROM(first(cons(y0, y1), cons(y2, y3))) -> c3(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FROM(first(first(y0, first(y1, y2)), y3)) -> c3(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FROM(first(first(y0, from(y1)), y2)) -> c3(MARK(first(first(y0, from(y1)), y2)))
   A__FROM(first(first(y0, 0), y1)) -> c3(MARK(first(first(y0, 0), y1)))
   A__FROM(first(first(y0, nil), y1)) -> c3(MARK(first(first(y0, nil), y1)))
   A__FROM(first(first(y0, s(y1)), y2)) -> c3(MARK(first(first(y0, s(y1)), y2)))
   A__FROM(first(first(y0, cons(y1, y2)), y3)) -> c3(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FROM(first(first(first(y0, y1), y2), y3)) -> c3(MARK(first(first(first(y0, y1), y2), y3)))
   A__FROM(first(first(from(y0), y1), y2)) -> c3(MARK(first(first(from(y0), y1), y2)))
   A__FROM(first(first(0, y0), y1)) -> c3(MARK(first(first(0, y0), y1)))
   A__FROM(first(first(nil, y0), y1)) -> c3(MARK(first(first(nil, y0), y1)))
   A__FROM(first(first(s(y0), y1), y2)) -> c3(MARK(first(first(s(y0), y1), y2)))
   A__FROM(first(first(cons(y0, y1), y2), y3)) -> c3(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FROM(first(first(y0, y1), 0)) -> c3(MARK(first(first(y0, y1), 0)))
   A__FROM(first(first(y0, y1), nil)) -> c3(MARK(first(first(y0, y1), nil)))
   A__FROM(first(first(y0, y1), s(y2))) -> c3(MARK(first(first(y0, y1), s(y2))))
   A__FROM(first(first(y0, y1), y2)) -> c3(MARK(first(first(y0, y1), y2)))
   A__FROM(first(from(first(y0, y1)), y2)) -> c3(MARK(first(from(first(y0, y1)), y2)))
   A__FROM(first(from(from(y0)), y1)) -> c3(MARK(first(from(from(y0)), y1)))
   A__FROM(first(from(0), y0)) -> c3(MARK(first(from(0), y0)))
   A__FROM(first(from(nil), y0)) -> c3(MARK(first(from(nil), y0)))
   A__FROM(first(from(s(y0)), y1)) -> c3(MARK(first(from(s(y0)), y1)))
   A__FROM(first(from(cons(y0, y1)), y2)) -> c3(MARK(first(from(cons(y0, y1)), y2)))
   A__FROM(first(from(y0), y1)) -> c3(MARK(first(from(y0), y1)))
   A__FROM(first(from(y0), 0)) -> c3(MARK(first(from(y0), 0)))
   A__FROM(first(from(y0), nil)) -> c3(MARK(first(from(y0), nil)))
   A__FROM(first(from(y0), s(y1))) -> c3(MARK(first(from(y0), s(y1))))
   A__FROM(first(s(first(y0, y1)), y2)) -> c3(MARK(first(s(first(y0, y1)), y2)))
   A__FROM(first(s(from(y0)), y1)) -> c3(MARK(first(s(from(y0)), y1)))
   A__FROM(first(s(0), y0)) -> c3(MARK(first(s(0), y0)))
   A__FROM(first(s(nil), y0)) -> c3(MARK(first(s(nil), y0)))
   A__FROM(first(s(s(y0)), y1)) -> c3(MARK(first(s(s(y0)), y1)))
   A__FROM(first(s(cons(y0, y1)), y2)) -> c3(MARK(first(s(cons(y0, y1)), y2)))
   A__FROM(first(s(y0), y1)) -> c3(MARK(first(s(y0), y1)))
   A__FROM(first(s(y0), 0)) -> c3(MARK(first(s(y0), 0)))
   A__FROM(first(s(y0), nil)) -> c3(MARK(first(s(y0), nil)))
   A__FROM(first(s(y0), s(y1))) -> c3(MARK(first(s(y0), s(y1))))
   A__FROM(first(0, first(y0, y1))) -> c3(MARK(first(0, first(y0, y1))))
   A__FROM(first(nil, first(y0, y1))) -> c3(MARK(first(nil, first(y0, y1))))
   A__FROM(first(0, from(y0))) -> c3(MARK(first(0, from(y0))))
   A__FROM(first(nil, from(y0))) -> c3(MARK(first(nil, from(y0))))
   A__FROM(first(y0, cons(y1, y2))) -> c3(MARK(first(y0, cons(y1, y2))))
   A__FROM(first(0, cons(y0, y1))) -> c3(MARK(first(0, cons(y0, y1))))
   A__FROM(first(nil, cons(y0, y1))) -> c3(MARK(first(nil, cons(y0, y1))))
   A__FROM(first(y0, cons(0, y1))) -> c3(MARK(first(y0, cons(0, y1))))
   A__FROM(first(y0, cons(nil, y1))) -> c3(MARK(first(y0, cons(nil, y1))))
   MARK(from(first(z0, z1))) -> c7(A__FROM(a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(from(from(z0))) -> c7(A__FROM(a__from(mark(z0))), MARK(from(z0)))
   MARK(from(0)) -> c7(A__FROM(0), MARK(0))
   MARK(from(nil)) -> c7(A__FROM(nil), MARK(nil))
   MARK(from(s(z0))) -> c7(A__FROM(s(mark(z0))), MARK(s(z0)))
   MARK(from(cons(z0, z1))) -> c7(A__FROM(cons(mark(z0), z1)), MARK(cons(z0, z1)))
S tuples:
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
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   A__FIRST(s(z0), cons(first(first(y0, first(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(y0, from(y1)), y2), z2)) -> c1(MARK(first(first(y0, from(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, 0), y1), z2)) -> c1(MARK(first(first(y0, 0), y1)))
   A__FIRST(s(z0), cons(first(first(y0, nil), y1), z2)) -> c1(MARK(first(first(y0, nil), y1)))
   A__FIRST(s(z0), cons(first(first(y0, s(y1)), y2), z2)) -> c1(MARK(first(first(y0, s(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, cons(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(first(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(first(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(from(y0), y1), y2), z2)) -> c1(MARK(first(first(from(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(0, y0), y1), z2)) -> c1(MARK(first(first(0, y0), y1)))
   A__FIRST(s(z0), cons(first(first(nil, y0), y1), z2)) -> c1(MARK(first(first(nil, y0), y1)))
   A__FIRST(s(z0), cons(first(first(s(y0), y1), y2), z2)) -> c1(MARK(first(first(s(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(cons(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(y0, y1), 0), z2)) -> c1(MARK(first(first(y0, y1), 0)))
   A__FIRST(s(z0), cons(first(first(y0, y1), nil), z2)) -> c1(MARK(first(first(y0, y1), nil)))
   A__FIRST(s(z0), cons(first(first(y0, y1), s(y2)), z2)) -> c1(MARK(first(first(y0, y1), s(y2))))
   A__FIRST(s(z0), cons(first(first(y0, y1), y2), z2)) -> c1(MARK(first(first(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(from(first(y0, y1)), y2), z2)) -> c1(MARK(first(from(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(from(y0)), y1), z2)) -> c1(MARK(first(from(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(0), y0), z2)) -> c1(MARK(first(from(0), y0)))
   A__FIRST(s(z0), cons(first(from(nil), y0), z2)) -> c1(MARK(first(from(nil), y0)))
   A__FIRST(s(z0), cons(first(from(s(y0)), y1), z2)) -> c1(MARK(first(from(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(cons(y0, y1)), y2), z2)) -> c1(MARK(first(from(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(y0), y1), z2)) -> c1(MARK(first(from(y0), y1)))
   A__FIRST(s(z0), cons(first(from(y0), 0), z2)) -> c1(MARK(first(from(y0), 0)))
   A__FIRST(s(z0), cons(first(from(y0), nil), z2)) -> c1(MARK(first(from(y0), nil)))
   A__FIRST(s(z0), cons(first(from(y0), s(y1)), z2)) -> c1(MARK(first(from(y0), s(y1))))
   A__FIRST(s(z0), cons(first(s(first(y0, y1)), y2), z2)) -> c1(MARK(first(s(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(from(y0)), y1), z2)) -> c1(MARK(first(s(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(0), y0), z2)) -> c1(MARK(first(s(0), y0)))
   A__FIRST(s(z0), cons(first(s(nil), y0), z2)) -> c1(MARK(first(s(nil), y0)))
   A__FIRST(s(z0), cons(first(s(s(y0)), y1), z2)) -> c1(MARK(first(s(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(cons(y0, y1)), y2), z2)) -> c1(MARK(first(s(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(y0), y1), z2)) -> c1(MARK(first(s(y0), y1)))
   A__FIRST(s(z0), cons(first(s(y0), 0), z2)) -> c1(MARK(first(s(y0), 0)))
   A__FIRST(s(z0), cons(first(s(y0), nil), z2)) -> c1(MARK(first(s(y0), nil)))
   A__FIRST(s(z0), cons(first(s(y0), s(y1)), z2)) -> c1(MARK(first(s(y0), s(y1))))
   A__FIRST(s(z0), cons(first(0, first(y0, y1)), z2)) -> c1(MARK(first(0, first(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, first(y0, y1)), z2)) -> c1(MARK(first(nil, first(y0, y1))))
   A__FIRST(s(z0), cons(first(0, from(y0)), z2)) -> c1(MARK(first(0, from(y0))))
   A__FIRST(s(z0), cons(first(nil, from(y0)), z2)) -> c1(MARK(first(nil, from(y0))))
   A__FIRST(s(z0), cons(first(y0, cons(y1, y2)), z2)) -> c1(MARK(first(y0, cons(y1, y2))))
   A__FIRST(s(z0), cons(first(0, cons(y0, y1)), z2)) -> c1(MARK(first(0, cons(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, cons(y0, y1)), z2)) -> c1(MARK(first(nil, cons(y0, y1))))
   MARK(first(x0, cons(0, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c6(MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(MARK(cons(nil, x2)))
   A__FROM(from(y0)) -> c3(MARK(from(y0)))
   A__FROM(s(y0)) -> c3(MARK(s(y0)))
   A__FROM(cons(y0, y1)) -> c3(MARK(cons(y0, y1)))
   A__FROM(first(y0, 0)) -> c3(MARK(first(y0, 0)))
   A__FROM(first(y0, nil)) -> c3(MARK(first(y0, nil)))
   A__FROM(first(y0, s(y1))) -> c3(MARK(first(y0, s(y1))))
   A__FROM(first(cons(y0, y1), y2)) -> c3(MARK(first(cons(y0, y1), y2)))
   A__FROM(first(0, y0)) -> c3(MARK(first(0, y0)))
   A__FROM(first(nil, y0)) -> c3(MARK(first(nil, y0)))
   A__FROM(first(y0, first(y1, first(y2, y3)))) -> c3(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FROM(first(y0, first(y1, from(y2)))) -> c3(MARK(first(y0, first(y1, from(y2)))))
   A__FROM(first(y0, first(y1, 0))) -> c3(MARK(first(y0, first(y1, 0))))
   A__FROM(first(y0, first(y1, nil))) -> c3(MARK(first(y0, first(y1, nil))))
   A__FROM(first(y0, first(y1, s(y2)))) -> c3(MARK(first(y0, first(y1, s(y2)))))
   A__FROM(first(y0, first(y1, cons(y2, y3)))) -> c3(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FROM(first(y0, first(first(y1, y2), y3))) -> c3(MARK(first(y0, first(first(y1, y2), y3))))
   A__FROM(first(y0, first(from(y1), y2))) -> c3(MARK(first(y0, first(from(y1), y2))))
   A__FROM(first(y0, first(0, y1))) -> c3(MARK(first(y0, first(0, y1))))
   A__FROM(first(y0, first(nil, y1))) -> c3(MARK(first(y0, first(nil, y1))))
   A__FROM(first(y0, first(s(y1), y2))) -> c3(MARK(first(y0, first(s(y1), y2))))
   A__FROM(first(y0, first(cons(y1, y2), y3))) -> c3(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), first(y2, y3))) -> c3(MARK(first(first(y0, y1), first(y2, y3))))
   A__FROM(first(from(y0), first(y1, y2))) -> c3(MARK(first(from(y0), first(y1, y2))))
   A__FROM(first(s(y0), first(y1, y2))) -> c3(MARK(first(s(y0), first(y1, y2))))
   A__FROM(first(y0, first(y1, y2))) -> c3(MARK(first(y0, first(y1, y2))))
   A__FROM(first(cons(y0, y1), first(y2, y3))) -> c3(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FROM(first(y0, from(y1))) -> c3(MARK(first(y0, from(y1))))
   A__FROM(first(y0, from(first(y1, y2)))) -> c3(MARK(first(y0, from(first(y1, y2)))))
   A__FROM(first(y0, from(from(y1)))) -> c3(MARK(first(y0, from(from(y1)))))
   A__FROM(first(y0, from(0))) -> c3(MARK(first(y0, from(0))))
   A__FROM(first(y0, from(nil))) -> c3(MARK(first(y0, from(nil))))
   A__FROM(first(y0, from(s(y1)))) -> c3(MARK(first(y0, from(s(y1)))))
   A__FROM(first(y0, from(cons(y1, y2)))) -> c3(MARK(first(y0, from(cons(y1, y2)))))
   A__FROM(first(first(y0, y1), from(y2))) -> c3(MARK(first(first(y0, y1), from(y2))))
   A__FROM(first(from(y0), from(y1))) -> c3(MARK(first(from(y0), from(y1))))
   A__FROM(first(s(y0), from(y1))) -> c3(MARK(first(s(y0), from(y1))))
   A__FROM(first(cons(y0, y1), from(y2))) -> c3(MARK(first(cons(y0, y1), from(y2))))
   A__FROM(first(y0, cons(first(y1, y2), y3))) -> c3(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FROM(first(y0, cons(from(y1), y2))) -> c3(MARK(first(y0, cons(from(y1), y2))))
   A__FROM(first(y0, cons(s(y1), y2))) -> c3(MARK(first(y0, cons(s(y1), y2))))
   A__FROM(first(y0, cons(cons(y1, y2), y3))) -> c3(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), cons(y2, y3))) -> c3(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FROM(first(from(y0), cons(y1, y2))) -> c3(MARK(first(from(y0), cons(y1, y2))))
   A__FROM(first(s(y0), cons(y1, y2))) -> c3(MARK(first(s(y0), cons(y1, y2))))
   A__FROM(first(cons(y0, y1), cons(y2, y3))) -> c3(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FROM(first(first(y0, first(y1, y2)), y3)) -> c3(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FROM(first(first(y0, from(y1)), y2)) -> c3(MARK(first(first(y0, from(y1)), y2)))
   A__FROM(first(first(y0, 0), y1)) -> c3(MARK(first(first(y0, 0), y1)))
   A__FROM(first(first(y0, nil), y1)) -> c3(MARK(first(first(y0, nil), y1)))
   A__FROM(first(first(y0, s(y1)), y2)) -> c3(MARK(first(first(y0, s(y1)), y2)))
   A__FROM(first(first(y0, cons(y1, y2)), y3)) -> c3(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FROM(first(first(first(y0, y1), y2), y3)) -> c3(MARK(first(first(first(y0, y1), y2), y3)))
   A__FROM(first(first(from(y0), y1), y2)) -> c3(MARK(first(first(from(y0), y1), y2)))
   A__FROM(first(first(0, y0), y1)) -> c3(MARK(first(first(0, y0), y1)))
   A__FROM(first(first(nil, y0), y1)) -> c3(MARK(first(first(nil, y0), y1)))
   A__FROM(first(first(s(y0), y1), y2)) -> c3(MARK(first(first(s(y0), y1), y2)))
   A__FROM(first(first(cons(y0, y1), y2), y3)) -> c3(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FROM(first(first(y0, y1), 0)) -> c3(MARK(first(first(y0, y1), 0)))
   A__FROM(first(first(y0, y1), nil)) -> c3(MARK(first(first(y0, y1), nil)))
   A__FROM(first(first(y0, y1), s(y2))) -> c3(MARK(first(first(y0, y1), s(y2))))
   A__FROM(first(first(y0, y1), y2)) -> c3(MARK(first(first(y0, y1), y2)))
   A__FROM(first(from(first(y0, y1)), y2)) -> c3(MARK(first(from(first(y0, y1)), y2)))
   A__FROM(first(from(from(y0)), y1)) -> c3(MARK(first(from(from(y0)), y1)))
   A__FROM(first(from(0), y0)) -> c3(MARK(first(from(0), y0)))
   A__FROM(first(from(nil), y0)) -> c3(MARK(first(from(nil), y0)))
   A__FROM(first(from(s(y0)), y1)) -> c3(MARK(first(from(s(y0)), y1)))
   A__FROM(first(from(cons(y0, y1)), y2)) -> c3(MARK(first(from(cons(y0, y1)), y2)))
   A__FROM(first(from(y0), y1)) -> c3(MARK(first(from(y0), y1)))
   A__FROM(first(from(y0), 0)) -> c3(MARK(first(from(y0), 0)))
   A__FROM(first(from(y0), nil)) -> c3(MARK(first(from(y0), nil)))
   A__FROM(first(from(y0), s(y1))) -> c3(MARK(first(from(y0), s(y1))))
   A__FROM(first(s(first(y0, y1)), y2)) -> c3(MARK(first(s(first(y0, y1)), y2)))
   A__FROM(first(s(from(y0)), y1)) -> c3(MARK(first(s(from(y0)), y1)))
   A__FROM(first(s(0), y0)) -> c3(MARK(first(s(0), y0)))
   A__FROM(first(s(nil), y0)) -> c3(MARK(first(s(nil), y0)))
   A__FROM(first(s(s(y0)), y1)) -> c3(MARK(first(s(s(y0)), y1)))
   A__FROM(first(s(cons(y0, y1)), y2)) -> c3(MARK(first(s(cons(y0, y1)), y2)))
   A__FROM(first(s(y0), y1)) -> c3(MARK(first(s(y0), y1)))
   A__FROM(first(s(y0), 0)) -> c3(MARK(first(s(y0), 0)))
   A__FROM(first(s(y0), nil)) -> c3(MARK(first(s(y0), nil)))
   A__FROM(first(s(y0), s(y1))) -> c3(MARK(first(s(y0), s(y1))))
   A__FROM(first(0, first(y0, y1))) -> c3(MARK(first(0, first(y0, y1))))
   A__FROM(first(nil, first(y0, y1))) -> c3(MARK(first(nil, first(y0, y1))))
   A__FROM(first(0, from(y0))) -> c3(MARK(first(0, from(y0))))
   A__FROM(first(nil, from(y0))) -> c3(MARK(first(nil, from(y0))))
   A__FROM(first(y0, cons(y1, y2))) -> c3(MARK(first(y0, cons(y1, y2))))
   A__FROM(first(0, cons(y0, y1))) -> c3(MARK(first(0, cons(y0, y1))))
   A__FROM(first(nil, cons(y0, y1))) -> c3(MARK(first(nil, cons(y0, y1))))
   A__FROM(first(y0, cons(0, y1))) -> c3(MARK(first(y0, cons(0, y1))))
   A__FROM(first(y0, cons(nil, y1))) -> c3(MARK(first(y0, cons(nil, y1))))
   MARK(from(first(z0, z1))) -> c7(A__FROM(a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(from(from(z0))) -> c7(A__FROM(a__from(mark(z0))), MARK(from(z0)))
   MARK(from(0)) -> c7(A__FROM(0), MARK(0))
   MARK(from(nil)) -> c7(A__FROM(nil), MARK(nil))
   MARK(from(s(z0))) -> c7(A__FROM(s(mark(z0))), MARK(s(z0)))
   MARK(from(cons(z0, z1))) -> c7(A__FROM(cons(mark(z0), z1)), MARK(cons(z0, z1)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   MARK_1, A__FIRST_2, A__FROM_1

Compound Symbols:   c10_1, c11_1, c5_1, c6_1, c5_2, c6_2, c1_1, c3_1, c7_2


----------------------------------------

(105) CdtLeafRemovalProof (BOTH BOUNDS(ID, ID))
Removed 2 trailing nodes:
   MARK(from(0)) -> c7(A__FROM(0), MARK(0))
   MARK(from(nil)) -> c7(A__FROM(nil), MARK(nil))

----------------------------------------

(106)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
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   A__FIRST(s(z0), cons(first(first(y0, nil), y1), z2)) -> c1(MARK(first(first(y0, nil), y1)))
   A__FIRST(s(z0), cons(first(first(y0, s(y1)), y2), z2)) -> c1(MARK(first(first(y0, s(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, cons(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(first(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(first(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(from(y0), y1), y2), z2)) -> c1(MARK(first(first(from(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(0, y0), y1), z2)) -> c1(MARK(first(first(0, y0), y1)))
   A__FIRST(s(z0), cons(first(first(nil, y0), y1), z2)) -> c1(MARK(first(first(nil, y0), y1)))
   A__FIRST(s(z0), cons(first(first(s(y0), y1), y2), z2)) -> c1(MARK(first(first(s(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(cons(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(y0, y1), 0), z2)) -> c1(MARK(first(first(y0, y1), 0)))
   A__FIRST(s(z0), cons(first(first(y0, y1), nil), z2)) -> c1(MARK(first(first(y0, y1), nil)))
   A__FIRST(s(z0), cons(first(first(y0, y1), s(y2)), z2)) -> c1(MARK(first(first(y0, y1), s(y2))))
   A__FIRST(s(z0), cons(first(first(y0, y1), y2), z2)) -> c1(MARK(first(first(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(from(first(y0, y1)), y2), z2)) -> c1(MARK(first(from(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(from(y0)), y1), z2)) -> c1(MARK(first(from(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(0), y0), z2)) -> c1(MARK(first(from(0), y0)))
   A__FIRST(s(z0), cons(first(from(nil), y0), z2)) -> c1(MARK(first(from(nil), y0)))
   A__FIRST(s(z0), cons(first(from(s(y0)), y1), z2)) -> c1(MARK(first(from(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(cons(y0, y1)), y2), z2)) -> c1(MARK(first(from(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(y0), y1), z2)) -> c1(MARK(first(from(y0), y1)))
   A__FIRST(s(z0), cons(first(from(y0), 0), z2)) -> c1(MARK(first(from(y0), 0)))
   A__FIRST(s(z0), cons(first(from(y0), nil), z2)) -> c1(MARK(first(from(y0), nil)))
   A__FIRST(s(z0), cons(first(from(y0), s(y1)), z2)) -> c1(MARK(first(from(y0), s(y1))))
   A__FIRST(s(z0), cons(first(s(first(y0, y1)), y2), z2)) -> c1(MARK(first(s(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(from(y0)), y1), z2)) -> c1(MARK(first(s(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(0), y0), z2)) -> c1(MARK(first(s(0), y0)))
   A__FIRST(s(z0), cons(first(s(nil), y0), z2)) -> c1(MARK(first(s(nil), y0)))
   A__FIRST(s(z0), cons(first(s(s(y0)), y1), z2)) -> c1(MARK(first(s(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(cons(y0, y1)), y2), z2)) -> c1(MARK(first(s(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(y0), y1), z2)) -> c1(MARK(first(s(y0), y1)))
   A__FIRST(s(z0), cons(first(s(y0), 0), z2)) -> c1(MARK(first(s(y0), 0)))
   A__FIRST(s(z0), cons(first(s(y0), nil), z2)) -> c1(MARK(first(s(y0), nil)))
   A__FIRST(s(z0), cons(first(s(y0), s(y1)), z2)) -> c1(MARK(first(s(y0), s(y1))))
   A__FIRST(s(z0), cons(first(0, first(y0, y1)), z2)) -> c1(MARK(first(0, first(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, first(y0, y1)), z2)) -> c1(MARK(first(nil, first(y0, y1))))
   A__FIRST(s(z0), cons(first(0, from(y0)), z2)) -> c1(MARK(first(0, from(y0))))
   A__FIRST(s(z0), cons(first(nil, from(y0)), z2)) -> c1(MARK(first(nil, from(y0))))
   A__FIRST(s(z0), cons(first(y0, cons(y1, y2)), z2)) -> c1(MARK(first(y0, cons(y1, y2))))
   A__FIRST(s(z0), cons(first(0, cons(y0, y1)), z2)) -> c1(MARK(first(0, cons(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, cons(y0, y1)), z2)) -> c1(MARK(first(nil, cons(y0, y1))))
   MARK(first(x0, cons(0, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c6(MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(MARK(cons(nil, x2)))
   A__FROM(from(y0)) -> c3(MARK(from(y0)))
   A__FROM(s(y0)) -> c3(MARK(s(y0)))
   A__FROM(cons(y0, y1)) -> c3(MARK(cons(y0, y1)))
   A__FROM(first(y0, 0)) -> c3(MARK(first(y0, 0)))
   A__FROM(first(y0, nil)) -> c3(MARK(first(y0, nil)))
   A__FROM(first(y0, s(y1))) -> c3(MARK(first(y0, s(y1))))
   A__FROM(first(cons(y0, y1), y2)) -> c3(MARK(first(cons(y0, y1), y2)))
   A__FROM(first(0, y0)) -> c3(MARK(first(0, y0)))
   A__FROM(first(nil, y0)) -> c3(MARK(first(nil, y0)))
   A__FROM(first(y0, first(y1, first(y2, y3)))) -> c3(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FROM(first(y0, first(y1, from(y2)))) -> c3(MARK(first(y0, first(y1, from(y2)))))
   A__FROM(first(y0, first(y1, 0))) -> c3(MARK(first(y0, first(y1, 0))))
   A__FROM(first(y0, first(y1, nil))) -> c3(MARK(first(y0, first(y1, nil))))
   A__FROM(first(y0, first(y1, s(y2)))) -> c3(MARK(first(y0, first(y1, s(y2)))))
   A__FROM(first(y0, first(y1, cons(y2, y3)))) -> c3(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FROM(first(y0, first(first(y1, y2), y3))) -> c3(MARK(first(y0, first(first(y1, y2), y3))))
   A__FROM(first(y0, first(from(y1), y2))) -> c3(MARK(first(y0, first(from(y1), y2))))
   A__FROM(first(y0, first(0, y1))) -> c3(MARK(first(y0, first(0, y1))))
   A__FROM(first(y0, first(nil, y1))) -> c3(MARK(first(y0, first(nil, y1))))
   A__FROM(first(y0, first(s(y1), y2))) -> c3(MARK(first(y0, first(s(y1), y2))))
   A__FROM(first(y0, first(cons(y1, y2), y3))) -> c3(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), first(y2, y3))) -> c3(MARK(first(first(y0, y1), first(y2, y3))))
   A__FROM(first(from(y0), first(y1, y2))) -> c3(MARK(first(from(y0), first(y1, y2))))
   A__FROM(first(s(y0), first(y1, y2))) -> c3(MARK(first(s(y0), first(y1, y2))))
   A__FROM(first(y0, first(y1, y2))) -> c3(MARK(first(y0, first(y1, y2))))
   A__FROM(first(cons(y0, y1), first(y2, y3))) -> c3(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FROM(first(y0, from(y1))) -> c3(MARK(first(y0, from(y1))))
   A__FROM(first(y0, from(first(y1, y2)))) -> c3(MARK(first(y0, from(first(y1, y2)))))
   A__FROM(first(y0, from(from(y1)))) -> c3(MARK(first(y0, from(from(y1)))))
   A__FROM(first(y0, from(0))) -> c3(MARK(first(y0, from(0))))
   A__FROM(first(y0, from(nil))) -> c3(MARK(first(y0, from(nil))))
   A__FROM(first(y0, from(s(y1)))) -> c3(MARK(first(y0, from(s(y1)))))
   A__FROM(first(y0, from(cons(y1, y2)))) -> c3(MARK(first(y0, from(cons(y1, y2)))))
   A__FROM(first(first(y0, y1), from(y2))) -> c3(MARK(first(first(y0, y1), from(y2))))
   A__FROM(first(from(y0), from(y1))) -> c3(MARK(first(from(y0), from(y1))))
   A__FROM(first(s(y0), from(y1))) -> c3(MARK(first(s(y0), from(y1))))
   A__FROM(first(cons(y0, y1), from(y2))) -> c3(MARK(first(cons(y0, y1), from(y2))))
   A__FROM(first(y0, cons(first(y1, y2), y3))) -> c3(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FROM(first(y0, cons(from(y1), y2))) -> c3(MARK(first(y0, cons(from(y1), y2))))
   A__FROM(first(y0, cons(s(y1), y2))) -> c3(MARK(first(y0, cons(s(y1), y2))))
   A__FROM(first(y0, cons(cons(y1, y2), y3))) -> c3(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), cons(y2, y3))) -> c3(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FROM(first(from(y0), cons(y1, y2))) -> c3(MARK(first(from(y0), cons(y1, y2))))
   A__FROM(first(s(y0), cons(y1, y2))) -> c3(MARK(first(s(y0), cons(y1, y2))))
   A__FROM(first(cons(y0, y1), cons(y2, y3))) -> c3(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FROM(first(first(y0, first(y1, y2)), y3)) -> c3(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FROM(first(first(y0, from(y1)), y2)) -> c3(MARK(first(first(y0, from(y1)), y2)))
   A__FROM(first(first(y0, 0), y1)) -> c3(MARK(first(first(y0, 0), y1)))
   A__FROM(first(first(y0, nil), y1)) -> c3(MARK(first(first(y0, nil), y1)))
   A__FROM(first(first(y0, s(y1)), y2)) -> c3(MARK(first(first(y0, s(y1)), y2)))
   A__FROM(first(first(y0, cons(y1, y2)), y3)) -> c3(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FROM(first(first(first(y0, y1), y2), y3)) -> c3(MARK(first(first(first(y0, y1), y2), y3)))
   A__FROM(first(first(from(y0), y1), y2)) -> c3(MARK(first(first(from(y0), y1), y2)))
   A__FROM(first(first(0, y0), y1)) -> c3(MARK(first(first(0, y0), y1)))
   A__FROM(first(first(nil, y0), y1)) -> c3(MARK(first(first(nil, y0), y1)))
   A__FROM(first(first(s(y0), y1), y2)) -> c3(MARK(first(first(s(y0), y1), y2)))
   A__FROM(first(first(cons(y0, y1), y2), y3)) -> c3(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FROM(first(first(y0, y1), 0)) -> c3(MARK(first(first(y0, y1), 0)))
   A__FROM(first(first(y0, y1), nil)) -> c3(MARK(first(first(y0, y1), nil)))
   A__FROM(first(first(y0, y1), s(y2))) -> c3(MARK(first(first(y0, y1), s(y2))))
   A__FROM(first(first(y0, y1), y2)) -> c3(MARK(first(first(y0, y1), y2)))
   A__FROM(first(from(first(y0, y1)), y2)) -> c3(MARK(first(from(first(y0, y1)), y2)))
   A__FROM(first(from(from(y0)), y1)) -> c3(MARK(first(from(from(y0)), y1)))
   A__FROM(first(from(0), y0)) -> c3(MARK(first(from(0), y0)))
   A__FROM(first(from(nil), y0)) -> c3(MARK(first(from(nil), y0)))
   A__FROM(first(from(s(y0)), y1)) -> c3(MARK(first(from(s(y0)), y1)))
   A__FROM(first(from(cons(y0, y1)), y2)) -> c3(MARK(first(from(cons(y0, y1)), y2)))
   A__FROM(first(from(y0), y1)) -> c3(MARK(first(from(y0), y1)))
   A__FROM(first(from(y0), 0)) -> c3(MARK(first(from(y0), 0)))
   A__FROM(first(from(y0), nil)) -> c3(MARK(first(from(y0), nil)))
   A__FROM(first(from(y0), s(y1))) -> c3(MARK(first(from(y0), s(y1))))
   A__FROM(first(s(first(y0, y1)), y2)) -> c3(MARK(first(s(first(y0, y1)), y2)))
   A__FROM(first(s(from(y0)), y1)) -> c3(MARK(first(s(from(y0)), y1)))
   A__FROM(first(s(0), y0)) -> c3(MARK(first(s(0), y0)))
   A__FROM(first(s(nil), y0)) -> c3(MARK(first(s(nil), y0)))
   A__FROM(first(s(s(y0)), y1)) -> c3(MARK(first(s(s(y0)), y1)))
   A__FROM(first(s(cons(y0, y1)), y2)) -> c3(MARK(first(s(cons(y0, y1)), y2)))
   A__FROM(first(s(y0), y1)) -> c3(MARK(first(s(y0), y1)))
   A__FROM(first(s(y0), 0)) -> c3(MARK(first(s(y0), 0)))
   A__FROM(first(s(y0), nil)) -> c3(MARK(first(s(y0), nil)))
   A__FROM(first(s(y0), s(y1))) -> c3(MARK(first(s(y0), s(y1))))
   A__FROM(first(0, first(y0, y1))) -> c3(MARK(first(0, first(y0, y1))))
   A__FROM(first(nil, first(y0, y1))) -> c3(MARK(first(nil, first(y0, y1))))
   A__FROM(first(0, from(y0))) -> c3(MARK(first(0, from(y0))))
   A__FROM(first(nil, from(y0))) -> c3(MARK(first(nil, from(y0))))
   A__FROM(first(y0, cons(y1, y2))) -> c3(MARK(first(y0, cons(y1, y2))))
   A__FROM(first(0, cons(y0, y1))) -> c3(MARK(first(0, cons(y0, y1))))
   A__FROM(first(nil, cons(y0, y1))) -> c3(MARK(first(nil, cons(y0, y1))))
   A__FROM(first(y0, cons(0, y1))) -> c3(MARK(first(y0, cons(0, y1))))
   A__FROM(first(y0, cons(nil, y1))) -> c3(MARK(first(y0, cons(nil, y1))))
   MARK(from(first(z0, z1))) -> c7(A__FROM(a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(from(from(z0))) -> c7(A__FROM(a__from(mark(z0))), MARK(from(z0)))
   MARK(from(s(z0))) -> c7(A__FROM(s(mark(z0))), MARK(s(z0)))
   MARK(from(cons(z0, z1))) -> c7(A__FROM(cons(mark(z0), z1)), MARK(cons(z0, z1)))
S tuples:
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
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   A__FIRST(s(z0), cons(first(first(y0, y1), 0), z2)) -> c1(MARK(first(first(y0, y1), 0)))
   A__FIRST(s(z0), cons(first(first(y0, y1), nil), z2)) -> c1(MARK(first(first(y0, y1), nil)))
   A__FIRST(s(z0), cons(first(first(y0, y1), s(y2)), z2)) -> c1(MARK(first(first(y0, y1), s(y2))))
   A__FIRST(s(z0), cons(first(first(y0, y1), y2), z2)) -> c1(MARK(first(first(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(from(first(y0, y1)), y2), z2)) -> c1(MARK(first(from(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(from(y0)), y1), z2)) -> c1(MARK(first(from(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(0), y0), z2)) -> c1(MARK(first(from(0), y0)))
   A__FIRST(s(z0), cons(first(from(nil), y0), z2)) -> c1(MARK(first(from(nil), y0)))
   A__FIRST(s(z0), cons(first(from(s(y0)), y1), z2)) -> c1(MARK(first(from(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(cons(y0, y1)), y2), z2)) -> c1(MARK(first(from(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(y0), y1), z2)) -> c1(MARK(first(from(y0), y1)))
   A__FIRST(s(z0), cons(first(from(y0), 0), z2)) -> c1(MARK(first(from(y0), 0)))
   A__FIRST(s(z0), cons(first(from(y0), nil), z2)) -> c1(MARK(first(from(y0), nil)))
   A__FIRST(s(z0), cons(first(from(y0), s(y1)), z2)) -> c1(MARK(first(from(y0), s(y1))))
   A__FIRST(s(z0), cons(first(s(first(y0, y1)), y2), z2)) -> c1(MARK(first(s(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(from(y0)), y1), z2)) -> c1(MARK(first(s(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(0), y0), z2)) -> c1(MARK(first(s(0), y0)))
   A__FIRST(s(z0), cons(first(s(nil), y0), z2)) -> c1(MARK(first(s(nil), y0)))
   A__FIRST(s(z0), cons(first(s(s(y0)), y1), z2)) -> c1(MARK(first(s(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(cons(y0, y1)), y2), z2)) -> c1(MARK(first(s(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(y0), y1), z2)) -> c1(MARK(first(s(y0), y1)))
   A__FIRST(s(z0), cons(first(s(y0), 0), z2)) -> c1(MARK(first(s(y0), 0)))
   A__FIRST(s(z0), cons(first(s(y0), nil), z2)) -> c1(MARK(first(s(y0), nil)))
   A__FIRST(s(z0), cons(first(s(y0), s(y1)), z2)) -> c1(MARK(first(s(y0), s(y1))))
   A__FIRST(s(z0), cons(first(0, first(y0, y1)), z2)) -> c1(MARK(first(0, first(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, first(y0, y1)), z2)) -> c1(MARK(first(nil, first(y0, y1))))
   A__FIRST(s(z0), cons(first(0, from(y0)), z2)) -> c1(MARK(first(0, from(y0))))
   A__FIRST(s(z0), cons(first(nil, from(y0)), z2)) -> c1(MARK(first(nil, from(y0))))
   A__FIRST(s(z0), cons(first(y0, cons(y1, y2)), z2)) -> c1(MARK(first(y0, cons(y1, y2))))
   A__FIRST(s(z0), cons(first(0, cons(y0, y1)), z2)) -> c1(MARK(first(0, cons(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, cons(y0, y1)), z2)) -> c1(MARK(first(nil, cons(y0, y1))))
   MARK(first(x0, cons(0, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c6(MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(MARK(cons(nil, x2)))
   A__FROM(from(y0)) -> c3(MARK(from(y0)))
   A__FROM(s(y0)) -> c3(MARK(s(y0)))
   A__FROM(cons(y0, y1)) -> c3(MARK(cons(y0, y1)))
   A__FROM(first(y0, 0)) -> c3(MARK(first(y0, 0)))
   A__FROM(first(y0, nil)) -> c3(MARK(first(y0, nil)))
   A__FROM(first(y0, s(y1))) -> c3(MARK(first(y0, s(y1))))
   A__FROM(first(cons(y0, y1), y2)) -> c3(MARK(first(cons(y0, y1), y2)))
   A__FROM(first(0, y0)) -> c3(MARK(first(0, y0)))
   A__FROM(first(nil, y0)) -> c3(MARK(first(nil, y0)))
   A__FROM(first(y0, first(y1, first(y2, y3)))) -> c3(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FROM(first(y0, first(y1, from(y2)))) -> c3(MARK(first(y0, first(y1, from(y2)))))
   A__FROM(first(y0, first(y1, 0))) -> c3(MARK(first(y0, first(y1, 0))))
   A__FROM(first(y0, first(y1, nil))) -> c3(MARK(first(y0, first(y1, nil))))
   A__FROM(first(y0, first(y1, s(y2)))) -> c3(MARK(first(y0, first(y1, s(y2)))))
   A__FROM(first(y0, first(y1, cons(y2, y3)))) -> c3(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FROM(first(y0, first(first(y1, y2), y3))) -> c3(MARK(first(y0, first(first(y1, y2), y3))))
   A__FROM(first(y0, first(from(y1), y2))) -> c3(MARK(first(y0, first(from(y1), y2))))
   A__FROM(first(y0, first(0, y1))) -> c3(MARK(first(y0, first(0, y1))))
   A__FROM(first(y0, first(nil, y1))) -> c3(MARK(first(y0, first(nil, y1))))
   A__FROM(first(y0, first(s(y1), y2))) -> c3(MARK(first(y0, first(s(y1), y2))))
   A__FROM(first(y0, first(cons(y1, y2), y3))) -> c3(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), first(y2, y3))) -> c3(MARK(first(first(y0, y1), first(y2, y3))))
   A__FROM(first(from(y0), first(y1, y2))) -> c3(MARK(first(from(y0), first(y1, y2))))
   A__FROM(first(s(y0), first(y1, y2))) -> c3(MARK(first(s(y0), first(y1, y2))))
   A__FROM(first(y0, first(y1, y2))) -> c3(MARK(first(y0, first(y1, y2))))
   A__FROM(first(cons(y0, y1), first(y2, y3))) -> c3(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FROM(first(y0, from(y1))) -> c3(MARK(first(y0, from(y1))))
   A__FROM(first(y0, from(first(y1, y2)))) -> c3(MARK(first(y0, from(first(y1, y2)))))
   A__FROM(first(y0, from(from(y1)))) -> c3(MARK(first(y0, from(from(y1)))))
   A__FROM(first(y0, from(0))) -> c3(MARK(first(y0, from(0))))
   A__FROM(first(y0, from(nil))) -> c3(MARK(first(y0, from(nil))))
   A__FROM(first(y0, from(s(y1)))) -> c3(MARK(first(y0, from(s(y1)))))
   A__FROM(first(y0, from(cons(y1, y2)))) -> c3(MARK(first(y0, from(cons(y1, y2)))))
   A__FROM(first(first(y0, y1), from(y2))) -> c3(MARK(first(first(y0, y1), from(y2))))
   A__FROM(first(from(y0), from(y1))) -> c3(MARK(first(from(y0), from(y1))))
   A__FROM(first(s(y0), from(y1))) -> c3(MARK(first(s(y0), from(y1))))
   A__FROM(first(cons(y0, y1), from(y2))) -> c3(MARK(first(cons(y0, y1), from(y2))))
   A__FROM(first(y0, cons(first(y1, y2), y3))) -> c3(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FROM(first(y0, cons(from(y1), y2))) -> c3(MARK(first(y0, cons(from(y1), y2))))
   A__FROM(first(y0, cons(s(y1), y2))) -> c3(MARK(first(y0, cons(s(y1), y2))))
   A__FROM(first(y0, cons(cons(y1, y2), y3))) -> c3(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), cons(y2, y3))) -> c3(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FROM(first(from(y0), cons(y1, y2))) -> c3(MARK(first(from(y0), cons(y1, y2))))
   A__FROM(first(s(y0), cons(y1, y2))) -> c3(MARK(first(s(y0), cons(y1, y2))))
   A__FROM(first(cons(y0, y1), cons(y2, y3))) -> c3(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FROM(first(first(y0, first(y1, y2)), y3)) -> c3(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FROM(first(first(y0, from(y1)), y2)) -> c3(MARK(first(first(y0, from(y1)), y2)))
   A__FROM(first(first(y0, 0), y1)) -> c3(MARK(first(first(y0, 0), y1)))
   A__FROM(first(first(y0, nil), y1)) -> c3(MARK(first(first(y0, nil), y1)))
   A__FROM(first(first(y0, s(y1)), y2)) -> c3(MARK(first(first(y0, s(y1)), y2)))
   A__FROM(first(first(y0, cons(y1, y2)), y3)) -> c3(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FROM(first(first(first(y0, y1), y2), y3)) -> c3(MARK(first(first(first(y0, y1), y2), y3)))
   A__FROM(first(first(from(y0), y1), y2)) -> c3(MARK(first(first(from(y0), y1), y2)))
   A__FROM(first(first(0, y0), y1)) -> c3(MARK(first(first(0, y0), y1)))
   A__FROM(first(first(nil, y0), y1)) -> c3(MARK(first(first(nil, y0), y1)))
   A__FROM(first(first(s(y0), y1), y2)) -> c3(MARK(first(first(s(y0), y1), y2)))
   A__FROM(first(first(cons(y0, y1), y2), y3)) -> c3(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FROM(first(first(y0, y1), 0)) -> c3(MARK(first(first(y0, y1), 0)))
   A__FROM(first(first(y0, y1), nil)) -> c3(MARK(first(first(y0, y1), nil)))
   A__FROM(first(first(y0, y1), s(y2))) -> c3(MARK(first(first(y0, y1), s(y2))))
   A__FROM(first(first(y0, y1), y2)) -> c3(MARK(first(first(y0, y1), y2)))
   A__FROM(first(from(first(y0, y1)), y2)) -> c3(MARK(first(from(first(y0, y1)), y2)))
   A__FROM(first(from(from(y0)), y1)) -> c3(MARK(first(from(from(y0)), y1)))
   A__FROM(first(from(0), y0)) -> c3(MARK(first(from(0), y0)))
   A__FROM(first(from(nil), y0)) -> c3(MARK(first(from(nil), y0)))
   A__FROM(first(from(s(y0)), y1)) -> c3(MARK(first(from(s(y0)), y1)))
   A__FROM(first(from(cons(y0, y1)), y2)) -> c3(MARK(first(from(cons(y0, y1)), y2)))
   A__FROM(first(from(y0), y1)) -> c3(MARK(first(from(y0), y1)))
   A__FROM(first(from(y0), 0)) -> c3(MARK(first(from(y0), 0)))
   A__FROM(first(from(y0), nil)) -> c3(MARK(first(from(y0), nil)))
   A__FROM(first(from(y0), s(y1))) -> c3(MARK(first(from(y0), s(y1))))
   A__FROM(first(s(first(y0, y1)), y2)) -> c3(MARK(first(s(first(y0, y1)), y2)))
   A__FROM(first(s(from(y0)), y1)) -> c3(MARK(first(s(from(y0)), y1)))
   A__FROM(first(s(0), y0)) -> c3(MARK(first(s(0), y0)))
   A__FROM(first(s(nil), y0)) -> c3(MARK(first(s(nil), y0)))
   A__FROM(first(s(s(y0)), y1)) -> c3(MARK(first(s(s(y0)), y1)))
   A__FROM(first(s(cons(y0, y1)), y2)) -> c3(MARK(first(s(cons(y0, y1)), y2)))
   A__FROM(first(s(y0), y1)) -> c3(MARK(first(s(y0), y1)))
   A__FROM(first(s(y0), 0)) -> c3(MARK(first(s(y0), 0)))
   A__FROM(first(s(y0), nil)) -> c3(MARK(first(s(y0), nil)))
   A__FROM(first(s(y0), s(y1))) -> c3(MARK(first(s(y0), s(y1))))
   A__FROM(first(0, first(y0, y1))) -> c3(MARK(first(0, first(y0, y1))))
   A__FROM(first(nil, first(y0, y1))) -> c3(MARK(first(nil, first(y0, y1))))
   A__FROM(first(0, from(y0))) -> c3(MARK(first(0, from(y0))))
   A__FROM(first(nil, from(y0))) -> c3(MARK(first(nil, from(y0))))
   A__FROM(first(y0, cons(y1, y2))) -> c3(MARK(first(y0, cons(y1, y2))))
   A__FROM(first(0, cons(y0, y1))) -> c3(MARK(first(0, cons(y0, y1))))
   A__FROM(first(nil, cons(y0, y1))) -> c3(MARK(first(nil, cons(y0, y1))))
   A__FROM(first(y0, cons(0, y1))) -> c3(MARK(first(y0, cons(0, y1))))
   A__FROM(first(y0, cons(nil, y1))) -> c3(MARK(first(y0, cons(nil, y1))))
   MARK(from(first(z0, z1))) -> c7(A__FROM(a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(from(from(z0))) -> c7(A__FROM(a__from(mark(z0))), MARK(from(z0)))
   MARK(from(s(z0))) -> c7(A__FROM(s(mark(z0))), MARK(s(z0)))
   MARK(from(cons(z0, z1))) -> c7(A__FROM(cons(mark(z0), z1)), MARK(cons(z0, z1)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   MARK_1, A__FIRST_2, A__FROM_1

Compound Symbols:   c10_1, c11_1, c5_1, c6_1, c5_2, c6_2, c1_1, c3_1, c7_2


----------------------------------------

(107) CdtRhsSimplificationProcessorProof (BOTH BOUNDS(ID, ID))
Removed 4 trailing tuple parts
----------------------------------------

(108)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
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   A__FIRST(s(z0), cons(first(from(0), y0), z2)) -> c1(MARK(first(from(0), y0)))
   A__FIRST(s(z0), cons(first(from(nil), y0), z2)) -> c1(MARK(first(from(nil), y0)))
   A__FIRST(s(z0), cons(first(from(s(y0)), y1), z2)) -> c1(MARK(first(from(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(cons(y0, y1)), y2), z2)) -> c1(MARK(first(from(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(y0), y1), z2)) -> c1(MARK(first(from(y0), y1)))
   A__FIRST(s(z0), cons(first(from(y0), 0), z2)) -> c1(MARK(first(from(y0), 0)))
   A__FIRST(s(z0), cons(first(from(y0), nil), z2)) -> c1(MARK(first(from(y0), nil)))
   A__FIRST(s(z0), cons(first(from(y0), s(y1)), z2)) -> c1(MARK(first(from(y0), s(y1))))
   A__FIRST(s(z0), cons(first(s(first(y0, y1)), y2), z2)) -> c1(MARK(first(s(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(from(y0)), y1), z2)) -> c1(MARK(first(s(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(0), y0), z2)) -> c1(MARK(first(s(0), y0)))
   A__FIRST(s(z0), cons(first(s(nil), y0), z2)) -> c1(MARK(first(s(nil), y0)))
   A__FIRST(s(z0), cons(first(s(s(y0)), y1), z2)) -> c1(MARK(first(s(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(cons(y0, y1)), y2), z2)) -> c1(MARK(first(s(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(y0), y1), z2)) -> c1(MARK(first(s(y0), y1)))
   A__FIRST(s(z0), cons(first(s(y0), 0), z2)) -> c1(MARK(first(s(y0), 0)))
   A__FIRST(s(z0), cons(first(s(y0), nil), z2)) -> c1(MARK(first(s(y0), nil)))
   A__FIRST(s(z0), cons(first(s(y0), s(y1)), z2)) -> c1(MARK(first(s(y0), s(y1))))
   A__FIRST(s(z0), cons(first(0, first(y0, y1)), z2)) -> c1(MARK(first(0, first(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, first(y0, y1)), z2)) -> c1(MARK(first(nil, first(y0, y1))))
   A__FIRST(s(z0), cons(first(0, from(y0)), z2)) -> c1(MARK(first(0, from(y0))))
   A__FIRST(s(z0), cons(first(nil, from(y0)), z2)) -> c1(MARK(first(nil, from(y0))))
   A__FIRST(s(z0), cons(first(y0, cons(y1, y2)), z2)) -> c1(MARK(first(y0, cons(y1, y2))))
   A__FIRST(s(z0), cons(first(0, cons(y0, y1)), z2)) -> c1(MARK(first(0, cons(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, cons(y0, y1)), z2)) -> c1(MARK(first(nil, cons(y0, y1))))
   MARK(first(x0, cons(0, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c6(MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(MARK(cons(nil, x2)))
   A__FROM(from(y0)) -> c3(MARK(from(y0)))
   A__FROM(s(y0)) -> c3(MARK(s(y0)))
   A__FROM(cons(y0, y1)) -> c3(MARK(cons(y0, y1)))
   A__FROM(first(y0, 0)) -> c3(MARK(first(y0, 0)))
   A__FROM(first(y0, nil)) -> c3(MARK(first(y0, nil)))
   A__FROM(first(y0, s(y1))) -> c3(MARK(first(y0, s(y1))))
   A__FROM(first(cons(y0, y1), y2)) -> c3(MARK(first(cons(y0, y1), y2)))
   A__FROM(first(0, y0)) -> c3(MARK(first(0, y0)))
   A__FROM(first(nil, y0)) -> c3(MARK(first(nil, y0)))
   A__FROM(first(y0, first(y1, first(y2, y3)))) -> c3(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FROM(first(y0, first(y1, from(y2)))) -> c3(MARK(first(y0, first(y1, from(y2)))))
   A__FROM(first(y0, first(y1, 0))) -> c3(MARK(first(y0, first(y1, 0))))
   A__FROM(first(y0, first(y1, nil))) -> c3(MARK(first(y0, first(y1, nil))))
   A__FROM(first(y0, first(y1, s(y2)))) -> c3(MARK(first(y0, first(y1, s(y2)))))
   A__FROM(first(y0, first(y1, cons(y2, y3)))) -> c3(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FROM(first(y0, first(first(y1, y2), y3))) -> c3(MARK(first(y0, first(first(y1, y2), y3))))
   A__FROM(first(y0, first(from(y1), y2))) -> c3(MARK(first(y0, first(from(y1), y2))))
   A__FROM(first(y0, first(0, y1))) -> c3(MARK(first(y0, first(0, y1))))
   A__FROM(first(y0, first(nil, y1))) -> c3(MARK(first(y0, first(nil, y1))))
   A__FROM(first(y0, first(s(y1), y2))) -> c3(MARK(first(y0, first(s(y1), y2))))
   A__FROM(first(y0, first(cons(y1, y2), y3))) -> c3(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), first(y2, y3))) -> c3(MARK(first(first(y0, y1), first(y2, y3))))
   A__FROM(first(from(y0), first(y1, y2))) -> c3(MARK(first(from(y0), first(y1, y2))))
   A__FROM(first(s(y0), first(y1, y2))) -> c3(MARK(first(s(y0), first(y1, y2))))
   A__FROM(first(y0, first(y1, y2))) -> c3(MARK(first(y0, first(y1, y2))))
   A__FROM(first(cons(y0, y1), first(y2, y3))) -> c3(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FROM(first(y0, from(y1))) -> c3(MARK(first(y0, from(y1))))
   A__FROM(first(y0, from(first(y1, y2)))) -> c3(MARK(first(y0, from(first(y1, y2)))))
   A__FROM(first(y0, from(from(y1)))) -> c3(MARK(first(y0, from(from(y1)))))
   A__FROM(first(y0, from(0))) -> c3(MARK(first(y0, from(0))))
   A__FROM(first(y0, from(nil))) -> c3(MARK(first(y0, from(nil))))
   A__FROM(first(y0, from(s(y1)))) -> c3(MARK(first(y0, from(s(y1)))))
   A__FROM(first(y0, from(cons(y1, y2)))) -> c3(MARK(first(y0, from(cons(y1, y2)))))
   A__FROM(first(first(y0, y1), from(y2))) -> c3(MARK(first(first(y0, y1), from(y2))))
   A__FROM(first(from(y0), from(y1))) -> c3(MARK(first(from(y0), from(y1))))
   A__FROM(first(s(y0), from(y1))) -> c3(MARK(first(s(y0), from(y1))))
   A__FROM(first(cons(y0, y1), from(y2))) -> c3(MARK(first(cons(y0, y1), from(y2))))
   A__FROM(first(y0, cons(first(y1, y2), y3))) -> c3(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FROM(first(y0, cons(from(y1), y2))) -> c3(MARK(first(y0, cons(from(y1), y2))))
   A__FROM(first(y0, cons(s(y1), y2))) -> c3(MARK(first(y0, cons(s(y1), y2))))
   A__FROM(first(y0, cons(cons(y1, y2), y3))) -> c3(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), cons(y2, y3))) -> c3(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FROM(first(from(y0), cons(y1, y2))) -> c3(MARK(first(from(y0), cons(y1, y2))))
   A__FROM(first(s(y0), cons(y1, y2))) -> c3(MARK(first(s(y0), cons(y1, y2))))
   A__FROM(first(cons(y0, y1), cons(y2, y3))) -> c3(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FROM(first(first(y0, first(y1, y2)), y3)) -> c3(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FROM(first(first(y0, from(y1)), y2)) -> c3(MARK(first(first(y0, from(y1)), y2)))
   A__FROM(first(first(y0, 0), y1)) -> c3(MARK(first(first(y0, 0), y1)))
   A__FROM(first(first(y0, nil), y1)) -> c3(MARK(first(first(y0, nil), y1)))
   A__FROM(first(first(y0, s(y1)), y2)) -> c3(MARK(first(first(y0, s(y1)), y2)))
   A__FROM(first(first(y0, cons(y1, y2)), y3)) -> c3(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FROM(first(first(first(y0, y1), y2), y3)) -> c3(MARK(first(first(first(y0, y1), y2), y3)))
   A__FROM(first(first(from(y0), y1), y2)) -> c3(MARK(first(first(from(y0), y1), y2)))
   A__FROM(first(first(0, y0), y1)) -> c3(MARK(first(first(0, y0), y1)))
   A__FROM(first(first(nil, y0), y1)) -> c3(MARK(first(first(nil, y0), y1)))
   A__FROM(first(first(s(y0), y1), y2)) -> c3(MARK(first(first(s(y0), y1), y2)))
   A__FROM(first(first(cons(y0, y1), y2), y3)) -> c3(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FROM(first(first(y0, y1), 0)) -> c3(MARK(first(first(y0, y1), 0)))
   A__FROM(first(first(y0, y1), nil)) -> c3(MARK(first(first(y0, y1), nil)))
   A__FROM(first(first(y0, y1), s(y2))) -> c3(MARK(first(first(y0, y1), s(y2))))
   A__FROM(first(first(y0, y1), y2)) -> c3(MARK(first(first(y0, y1), y2)))
   A__FROM(first(from(first(y0, y1)), y2)) -> c3(MARK(first(from(first(y0, y1)), y2)))
   A__FROM(first(from(from(y0)), y1)) -> c3(MARK(first(from(from(y0)), y1)))
   A__FROM(first(from(0), y0)) -> c3(MARK(first(from(0), y0)))
   A__FROM(first(from(nil), y0)) -> c3(MARK(first(from(nil), y0)))
   A__FROM(first(from(s(y0)), y1)) -> c3(MARK(first(from(s(y0)), y1)))
   A__FROM(first(from(cons(y0, y1)), y2)) -> c3(MARK(first(from(cons(y0, y1)), y2)))
   A__FROM(first(from(y0), y1)) -> c3(MARK(first(from(y0), y1)))
   A__FROM(first(from(y0), 0)) -> c3(MARK(first(from(y0), 0)))
   A__FROM(first(from(y0), nil)) -> c3(MARK(first(from(y0), nil)))
   A__FROM(first(from(y0), s(y1))) -> c3(MARK(first(from(y0), s(y1))))
   A__FROM(first(s(first(y0, y1)), y2)) -> c3(MARK(first(s(first(y0, y1)), y2)))
   A__FROM(first(s(from(y0)), y1)) -> c3(MARK(first(s(from(y0)), y1)))
   A__FROM(first(s(0), y0)) -> c3(MARK(first(s(0), y0)))
   A__FROM(first(s(nil), y0)) -> c3(MARK(first(s(nil), y0)))
   A__FROM(first(s(s(y0)), y1)) -> c3(MARK(first(s(s(y0)), y1)))
   A__FROM(first(s(cons(y0, y1)), y2)) -> c3(MARK(first(s(cons(y0, y1)), y2)))
   A__FROM(first(s(y0), y1)) -> c3(MARK(first(s(y0), y1)))
   A__FROM(first(s(y0), 0)) -> c3(MARK(first(s(y0), 0)))
   A__FROM(first(s(y0), nil)) -> c3(MARK(first(s(y0), nil)))
   A__FROM(first(s(y0), s(y1))) -> c3(MARK(first(s(y0), s(y1))))
   A__FROM(first(0, first(y0, y1))) -> c3(MARK(first(0, first(y0, y1))))
   A__FROM(first(nil, first(y0, y1))) -> c3(MARK(first(nil, first(y0, y1))))
   A__FROM(first(0, from(y0))) -> c3(MARK(first(0, from(y0))))
   A__FROM(first(nil, from(y0))) -> c3(MARK(first(nil, from(y0))))
   A__FROM(first(y0, cons(y1, y2))) -> c3(MARK(first(y0, cons(y1, y2))))
   A__FROM(first(0, cons(y0, y1))) -> c3(MARK(first(0, cons(y0, y1))))
   A__FROM(first(nil, cons(y0, y1))) -> c3(MARK(first(nil, cons(y0, y1))))
   A__FROM(first(y0, cons(0, y1))) -> c3(MARK(first(y0, cons(0, y1))))
   A__FROM(first(y0, cons(nil, y1))) -> c3(MARK(first(y0, cons(nil, y1))))
   MARK(from(first(z0, z1))) -> c7(A__FROM(a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(from(from(z0))) -> c7(A__FROM(a__from(mark(z0))), MARK(from(z0)))
   MARK(from(s(z0))) -> c7(A__FROM(s(mark(z0))), MARK(s(z0)))
   MARK(from(cons(z0, z1))) -> c7(A__FROM(cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)))
S tuples:
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
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   A__FIRST(s(z0), cons(first(s(y0), y1), z2)) -> c1(MARK(first(s(y0), y1)))
   A__FIRST(s(z0), cons(first(s(y0), 0), z2)) -> c1(MARK(first(s(y0), 0)))
   A__FIRST(s(z0), cons(first(s(y0), nil), z2)) -> c1(MARK(first(s(y0), nil)))
   A__FIRST(s(z0), cons(first(s(y0), s(y1)), z2)) -> c1(MARK(first(s(y0), s(y1))))
   A__FIRST(s(z0), cons(first(0, first(y0, y1)), z2)) -> c1(MARK(first(0, first(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, first(y0, y1)), z2)) -> c1(MARK(first(nil, first(y0, y1))))
   A__FIRST(s(z0), cons(first(0, from(y0)), z2)) -> c1(MARK(first(0, from(y0))))
   A__FIRST(s(z0), cons(first(nil, from(y0)), z2)) -> c1(MARK(first(nil, from(y0))))
   A__FIRST(s(z0), cons(first(y0, cons(y1, y2)), z2)) -> c1(MARK(first(y0, cons(y1, y2))))
   A__FIRST(s(z0), cons(first(0, cons(y0, y1)), z2)) -> c1(MARK(first(0, cons(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, cons(y0, y1)), z2)) -> c1(MARK(first(nil, cons(y0, y1))))
   MARK(first(x0, cons(0, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c6(MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(MARK(cons(nil, x2)))
   A__FROM(from(y0)) -> c3(MARK(from(y0)))
   A__FROM(s(y0)) -> c3(MARK(s(y0)))
   A__FROM(cons(y0, y1)) -> c3(MARK(cons(y0, y1)))
   A__FROM(first(y0, 0)) -> c3(MARK(first(y0, 0)))
   A__FROM(first(y0, nil)) -> c3(MARK(first(y0, nil)))
   A__FROM(first(y0, s(y1))) -> c3(MARK(first(y0, s(y1))))
   A__FROM(first(cons(y0, y1), y2)) -> c3(MARK(first(cons(y0, y1), y2)))
   A__FROM(first(0, y0)) -> c3(MARK(first(0, y0)))
   A__FROM(first(nil, y0)) -> c3(MARK(first(nil, y0)))
   A__FROM(first(y0, first(y1, first(y2, y3)))) -> c3(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FROM(first(y0, first(y1, from(y2)))) -> c3(MARK(first(y0, first(y1, from(y2)))))
   A__FROM(first(y0, first(y1, 0))) -> c3(MARK(first(y0, first(y1, 0))))
   A__FROM(first(y0, first(y1, nil))) -> c3(MARK(first(y0, first(y1, nil))))
   A__FROM(first(y0, first(y1, s(y2)))) -> c3(MARK(first(y0, first(y1, s(y2)))))
   A__FROM(first(y0, first(y1, cons(y2, y3)))) -> c3(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FROM(first(y0, first(first(y1, y2), y3))) -> c3(MARK(first(y0, first(first(y1, y2), y3))))
   A__FROM(first(y0, first(from(y1), y2))) -> c3(MARK(first(y0, first(from(y1), y2))))
   A__FROM(first(y0, first(0, y1))) -> c3(MARK(first(y0, first(0, y1))))
   A__FROM(first(y0, first(nil, y1))) -> c3(MARK(first(y0, first(nil, y1))))
   A__FROM(first(y0, first(s(y1), y2))) -> c3(MARK(first(y0, first(s(y1), y2))))
   A__FROM(first(y0, first(cons(y1, y2), y3))) -> c3(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), first(y2, y3))) -> c3(MARK(first(first(y0, y1), first(y2, y3))))
   A__FROM(first(from(y0), first(y1, y2))) -> c3(MARK(first(from(y0), first(y1, y2))))
   A__FROM(first(s(y0), first(y1, y2))) -> c3(MARK(first(s(y0), first(y1, y2))))
   A__FROM(first(y0, first(y1, y2))) -> c3(MARK(first(y0, first(y1, y2))))
   A__FROM(first(cons(y0, y1), first(y2, y3))) -> c3(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FROM(first(y0, from(y1))) -> c3(MARK(first(y0, from(y1))))
   A__FROM(first(y0, from(first(y1, y2)))) -> c3(MARK(first(y0, from(first(y1, y2)))))
   A__FROM(first(y0, from(from(y1)))) -> c3(MARK(first(y0, from(from(y1)))))
   A__FROM(first(y0, from(0))) -> c3(MARK(first(y0, from(0))))
   A__FROM(first(y0, from(nil))) -> c3(MARK(first(y0, from(nil))))
   A__FROM(first(y0, from(s(y1)))) -> c3(MARK(first(y0, from(s(y1)))))
   A__FROM(first(y0, from(cons(y1, y2)))) -> c3(MARK(first(y0, from(cons(y1, y2)))))
   A__FROM(first(first(y0, y1), from(y2))) -> c3(MARK(first(first(y0, y1), from(y2))))
   A__FROM(first(from(y0), from(y1))) -> c3(MARK(first(from(y0), from(y1))))
   A__FROM(first(s(y0), from(y1))) -> c3(MARK(first(s(y0), from(y1))))
   A__FROM(first(cons(y0, y1), from(y2))) -> c3(MARK(first(cons(y0, y1), from(y2))))
   A__FROM(first(y0, cons(first(y1, y2), y3))) -> c3(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FROM(first(y0, cons(from(y1), y2))) -> c3(MARK(first(y0, cons(from(y1), y2))))
   A__FROM(first(y0, cons(s(y1), y2))) -> c3(MARK(first(y0, cons(s(y1), y2))))
   A__FROM(first(y0, cons(cons(y1, y2), y3))) -> c3(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), cons(y2, y3))) -> c3(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FROM(first(from(y0), cons(y1, y2))) -> c3(MARK(first(from(y0), cons(y1, y2))))
   A__FROM(first(s(y0), cons(y1, y2))) -> c3(MARK(first(s(y0), cons(y1, y2))))
   A__FROM(first(cons(y0, y1), cons(y2, y3))) -> c3(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FROM(first(first(y0, first(y1, y2)), y3)) -> c3(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FROM(first(first(y0, from(y1)), y2)) -> c3(MARK(first(first(y0, from(y1)), y2)))
   A__FROM(first(first(y0, 0), y1)) -> c3(MARK(first(first(y0, 0), y1)))
   A__FROM(first(first(y0, nil), y1)) -> c3(MARK(first(first(y0, nil), y1)))
   A__FROM(first(first(y0, s(y1)), y2)) -> c3(MARK(first(first(y0, s(y1)), y2)))
   A__FROM(first(first(y0, cons(y1, y2)), y3)) -> c3(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FROM(first(first(first(y0, y1), y2), y3)) -> c3(MARK(first(first(first(y0, y1), y2), y3)))
   A__FROM(first(first(from(y0), y1), y2)) -> c3(MARK(first(first(from(y0), y1), y2)))
   A__FROM(first(first(0, y0), y1)) -> c3(MARK(first(first(0, y0), y1)))
   A__FROM(first(first(nil, y0), y1)) -> c3(MARK(first(first(nil, y0), y1)))
   A__FROM(first(first(s(y0), y1), y2)) -> c3(MARK(first(first(s(y0), y1), y2)))
   A__FROM(first(first(cons(y0, y1), y2), y3)) -> c3(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FROM(first(first(y0, y1), 0)) -> c3(MARK(first(first(y0, y1), 0)))
   A__FROM(first(first(y0, y1), nil)) -> c3(MARK(first(first(y0, y1), nil)))
   A__FROM(first(first(y0, y1), s(y2))) -> c3(MARK(first(first(y0, y1), s(y2))))
   A__FROM(first(first(y0, y1), y2)) -> c3(MARK(first(first(y0, y1), y2)))
   A__FROM(first(from(first(y0, y1)), y2)) -> c3(MARK(first(from(first(y0, y1)), y2)))
   A__FROM(first(from(from(y0)), y1)) -> c3(MARK(first(from(from(y0)), y1)))
   A__FROM(first(from(0), y0)) -> c3(MARK(first(from(0), y0)))
   A__FROM(first(from(nil), y0)) -> c3(MARK(first(from(nil), y0)))
   A__FROM(first(from(s(y0)), y1)) -> c3(MARK(first(from(s(y0)), y1)))
   A__FROM(first(from(cons(y0, y1)), y2)) -> c3(MARK(first(from(cons(y0, y1)), y2)))
   A__FROM(first(from(y0), y1)) -> c3(MARK(first(from(y0), y1)))
   A__FROM(first(from(y0), 0)) -> c3(MARK(first(from(y0), 0)))
   A__FROM(first(from(y0), nil)) -> c3(MARK(first(from(y0), nil)))
   A__FROM(first(from(y0), s(y1))) -> c3(MARK(first(from(y0), s(y1))))
   A__FROM(first(s(first(y0, y1)), y2)) -> c3(MARK(first(s(first(y0, y1)), y2)))
   A__FROM(first(s(from(y0)), y1)) -> c3(MARK(first(s(from(y0)), y1)))
   A__FROM(first(s(0), y0)) -> c3(MARK(first(s(0), y0)))
   A__FROM(first(s(nil), y0)) -> c3(MARK(first(s(nil), y0)))
   A__FROM(first(s(s(y0)), y1)) -> c3(MARK(first(s(s(y0)), y1)))
   A__FROM(first(s(cons(y0, y1)), y2)) -> c3(MARK(first(s(cons(y0, y1)), y2)))
   A__FROM(first(s(y0), y1)) -> c3(MARK(first(s(y0), y1)))
   A__FROM(first(s(y0), 0)) -> c3(MARK(first(s(y0), 0)))
   A__FROM(first(s(y0), nil)) -> c3(MARK(first(s(y0), nil)))
   A__FROM(first(s(y0), s(y1))) -> c3(MARK(first(s(y0), s(y1))))
   A__FROM(first(0, first(y0, y1))) -> c3(MARK(first(0, first(y0, y1))))
   A__FROM(first(nil, first(y0, y1))) -> c3(MARK(first(nil, first(y0, y1))))
   A__FROM(first(0, from(y0))) -> c3(MARK(first(0, from(y0))))
   A__FROM(first(nil, from(y0))) -> c3(MARK(first(nil, from(y0))))
   A__FROM(first(y0, cons(y1, y2))) -> c3(MARK(first(y0, cons(y1, y2))))
   A__FROM(first(0, cons(y0, y1))) -> c3(MARK(first(0, cons(y0, y1))))
   A__FROM(first(nil, cons(y0, y1))) -> c3(MARK(first(nil, cons(y0, y1))))
   A__FROM(first(y0, cons(0, y1))) -> c3(MARK(first(y0, cons(0, y1))))
   A__FROM(first(y0, cons(nil, y1))) -> c3(MARK(first(y0, cons(nil, y1))))
   MARK(from(first(z0, z1))) -> c7(A__FROM(a__first(mark(z0), mark(z1))), MARK(first(z0, z1)))
   MARK(from(from(z0))) -> c7(A__FROM(a__from(mark(z0))), MARK(from(z0)))
   MARK(from(s(z0))) -> c7(A__FROM(s(mark(z0))), MARK(s(z0)))
   MARK(from(cons(z0, z1))) -> c7(A__FROM(cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   MARK_1, A__FIRST_2, A__FROM_1

Compound Symbols:   c10_1, c11_1, c5_1, c6_1, c5_2, c6_2, c1_1, c3_1, c7_2


----------------------------------------

(109) CdtNarrowingProof (BOTH BOUNDS(ID, ID))
Use narrowing to replace MARK(from(first(z0, z1))) -> c7(A__FROM(a__first(mark(z0), mark(z1))), MARK(first(z0, z1))) by 
   MARK(from(first(x0, x1))) -> c7(A__FROM(first(mark(x0), mark(x1))), MARK(first(x0, x1)))
   MARK(from(first(x0, first(z0, z1)))) -> c7(A__FROM(a__first(mark(x0), a__first(mark(z0), mark(z1)))), MARK(first(x0, first(z0, z1))))
   MARK(from(first(x0, from(z0)))) -> c7(A__FROM(a__first(mark(x0), a__from(mark(z0)))), MARK(first(x0, from(z0))))
   MARK(from(first(x0, 0))) -> c7(A__FROM(a__first(mark(x0), 0)), MARK(first(x0, 0)))
   MARK(from(first(x0, nil))) -> c7(A__FROM(a__first(mark(x0), nil)), MARK(first(x0, nil)))
   MARK(from(first(x0, s(z0)))) -> c7(A__FROM(a__first(mark(x0), s(mark(z0)))), MARK(first(x0, s(z0))))
   MARK(from(first(x0, cons(z0, z1)))) -> c7(A__FROM(a__first(mark(x0), cons(mark(z0), z1))), MARK(first(x0, cons(z0, z1))))
   MARK(from(first(first(z0, z1), x1))) -> c7(A__FROM(a__first(a__first(mark(z0), mark(z1)), mark(x1))), MARK(first(first(z0, z1), x1)))
   MARK(from(first(from(z0), x1))) -> c7(A__FROM(a__first(a__from(mark(z0)), mark(x1))), MARK(first(from(z0), x1)))
   MARK(from(first(0, x1))) -> c7(A__FROM(a__first(0, mark(x1))), MARK(first(0, x1)))
   MARK(from(first(nil, x1))) -> c7(A__FROM(a__first(nil, mark(x1))), MARK(first(nil, x1)))
   MARK(from(first(s(z0), x1))) -> c7(A__FROM(a__first(s(mark(z0)), mark(x1))), MARK(first(s(z0), x1)))
   MARK(from(first(cons(z0, z1), x1))) -> c7(A__FROM(a__first(cons(mark(z0), z1), mark(x1))), MARK(first(cons(z0, z1), x1)))

----------------------------------------

(110)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
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   A__FIRST(s(z0), cons(first(from(nil), y0), z2)) -> c1(MARK(first(from(nil), y0)))
   A__FIRST(s(z0), cons(first(from(s(y0)), y1), z2)) -> c1(MARK(first(from(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(cons(y0, y1)), y2), z2)) -> c1(MARK(first(from(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(y0), y1), z2)) -> c1(MARK(first(from(y0), y1)))
   A__FIRST(s(z0), cons(first(from(y0), 0), z2)) -> c1(MARK(first(from(y0), 0)))
   A__FIRST(s(z0), cons(first(from(y0), nil), z2)) -> c1(MARK(first(from(y0), nil)))
   A__FIRST(s(z0), cons(first(from(y0), s(y1)), z2)) -> c1(MARK(first(from(y0), s(y1))))
   A__FIRST(s(z0), cons(first(s(first(y0, y1)), y2), z2)) -> c1(MARK(first(s(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(from(y0)), y1), z2)) -> c1(MARK(first(s(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(0), y0), z2)) -> c1(MARK(first(s(0), y0)))
   A__FIRST(s(z0), cons(first(s(nil), y0), z2)) -> c1(MARK(first(s(nil), y0)))
   A__FIRST(s(z0), cons(first(s(s(y0)), y1), z2)) -> c1(MARK(first(s(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(cons(y0, y1)), y2), z2)) -> c1(MARK(first(s(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(y0), y1), z2)) -> c1(MARK(first(s(y0), y1)))
   A__FIRST(s(z0), cons(first(s(y0), 0), z2)) -> c1(MARK(first(s(y0), 0)))
   A__FIRST(s(z0), cons(first(s(y0), nil), z2)) -> c1(MARK(first(s(y0), nil)))
   A__FIRST(s(z0), cons(first(s(y0), s(y1)), z2)) -> c1(MARK(first(s(y0), s(y1))))
   A__FIRST(s(z0), cons(first(0, first(y0, y1)), z2)) -> c1(MARK(first(0, first(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, first(y0, y1)), z2)) -> c1(MARK(first(nil, first(y0, y1))))
   A__FIRST(s(z0), cons(first(0, from(y0)), z2)) -> c1(MARK(first(0, from(y0))))
   A__FIRST(s(z0), cons(first(nil, from(y0)), z2)) -> c1(MARK(first(nil, from(y0))))
   A__FIRST(s(z0), cons(first(y0, cons(y1, y2)), z2)) -> c1(MARK(first(y0, cons(y1, y2))))
   A__FIRST(s(z0), cons(first(0, cons(y0, y1)), z2)) -> c1(MARK(first(0, cons(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, cons(y0, y1)), z2)) -> c1(MARK(first(nil, cons(y0, y1))))
   MARK(first(x0, cons(0, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c6(MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(MARK(cons(nil, x2)))
   A__FROM(from(y0)) -> c3(MARK(from(y0)))
   A__FROM(s(y0)) -> c3(MARK(s(y0)))
   A__FROM(cons(y0, y1)) -> c3(MARK(cons(y0, y1)))
   A__FROM(first(y0, 0)) -> c3(MARK(first(y0, 0)))
   A__FROM(first(y0, nil)) -> c3(MARK(first(y0, nil)))
   A__FROM(first(y0, s(y1))) -> c3(MARK(first(y0, s(y1))))
   A__FROM(first(cons(y0, y1), y2)) -> c3(MARK(first(cons(y0, y1), y2)))
   A__FROM(first(0, y0)) -> c3(MARK(first(0, y0)))
   A__FROM(first(nil, y0)) -> c3(MARK(first(nil, y0)))
   A__FROM(first(y0, first(y1, first(y2, y3)))) -> c3(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FROM(first(y0, first(y1, from(y2)))) -> c3(MARK(first(y0, first(y1, from(y2)))))
   A__FROM(first(y0, first(y1, 0))) -> c3(MARK(first(y0, first(y1, 0))))
   A__FROM(first(y0, first(y1, nil))) -> c3(MARK(first(y0, first(y1, nil))))
   A__FROM(first(y0, first(y1, s(y2)))) -> c3(MARK(first(y0, first(y1, s(y2)))))
   A__FROM(first(y0, first(y1, cons(y2, y3)))) -> c3(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FROM(first(y0, first(first(y1, y2), y3))) -> c3(MARK(first(y0, first(first(y1, y2), y3))))
   A__FROM(first(y0, first(from(y1), y2))) -> c3(MARK(first(y0, first(from(y1), y2))))
   A__FROM(first(y0, first(0, y1))) -> c3(MARK(first(y0, first(0, y1))))
   A__FROM(first(y0, first(nil, y1))) -> c3(MARK(first(y0, first(nil, y1))))
   A__FROM(first(y0, first(s(y1), y2))) -> c3(MARK(first(y0, first(s(y1), y2))))
   A__FROM(first(y0, first(cons(y1, y2), y3))) -> c3(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), first(y2, y3))) -> c3(MARK(first(first(y0, y1), first(y2, y3))))
   A__FROM(first(from(y0), first(y1, y2))) -> c3(MARK(first(from(y0), first(y1, y2))))
   A__FROM(first(s(y0), first(y1, y2))) -> c3(MARK(first(s(y0), first(y1, y2))))
   A__FROM(first(y0, first(y1, y2))) -> c3(MARK(first(y0, first(y1, y2))))
   A__FROM(first(cons(y0, y1), first(y2, y3))) -> c3(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FROM(first(y0, from(y1))) -> c3(MARK(first(y0, from(y1))))
   A__FROM(first(y0, from(first(y1, y2)))) -> c3(MARK(first(y0, from(first(y1, y2)))))
   A__FROM(first(y0, from(from(y1)))) -> c3(MARK(first(y0, from(from(y1)))))
   A__FROM(first(y0, from(0))) -> c3(MARK(first(y0, from(0))))
   A__FROM(first(y0, from(nil))) -> c3(MARK(first(y0, from(nil))))
   A__FROM(first(y0, from(s(y1)))) -> c3(MARK(first(y0, from(s(y1)))))
   A__FROM(first(y0, from(cons(y1, y2)))) -> c3(MARK(first(y0, from(cons(y1, y2)))))
   A__FROM(first(first(y0, y1), from(y2))) -> c3(MARK(first(first(y0, y1), from(y2))))
   A__FROM(first(from(y0), from(y1))) -> c3(MARK(first(from(y0), from(y1))))
   A__FROM(first(s(y0), from(y1))) -> c3(MARK(first(s(y0), from(y1))))
   A__FROM(first(cons(y0, y1), from(y2))) -> c3(MARK(first(cons(y0, y1), from(y2))))
   A__FROM(first(y0, cons(first(y1, y2), y3))) -> c3(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FROM(first(y0, cons(from(y1), y2))) -> c3(MARK(first(y0, cons(from(y1), y2))))
   A__FROM(first(y0, cons(s(y1), y2))) -> c3(MARK(first(y0, cons(s(y1), y2))))
   A__FROM(first(y0, cons(cons(y1, y2), y3))) -> c3(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), cons(y2, y3))) -> c3(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FROM(first(from(y0), cons(y1, y2))) -> c3(MARK(first(from(y0), cons(y1, y2))))
   A__FROM(first(s(y0), cons(y1, y2))) -> c3(MARK(first(s(y0), cons(y1, y2))))
   A__FROM(first(cons(y0, y1), cons(y2, y3))) -> c3(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FROM(first(first(y0, first(y1, y2)), y3)) -> c3(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FROM(first(first(y0, from(y1)), y2)) -> c3(MARK(first(first(y0, from(y1)), y2)))
   A__FROM(first(first(y0, 0), y1)) -> c3(MARK(first(first(y0, 0), y1)))
   A__FROM(first(first(y0, nil), y1)) -> c3(MARK(first(first(y0, nil), y1)))
   A__FROM(first(first(y0, s(y1)), y2)) -> c3(MARK(first(first(y0, s(y1)), y2)))
   A__FROM(first(first(y0, cons(y1, y2)), y3)) -> c3(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FROM(first(first(first(y0, y1), y2), y3)) -> c3(MARK(first(first(first(y0, y1), y2), y3)))
   A__FROM(first(first(from(y0), y1), y2)) -> c3(MARK(first(first(from(y0), y1), y2)))
   A__FROM(first(first(0, y0), y1)) -> c3(MARK(first(first(0, y0), y1)))
   A__FROM(first(first(nil, y0), y1)) -> c3(MARK(first(first(nil, y0), y1)))
   A__FROM(first(first(s(y0), y1), y2)) -> c3(MARK(first(first(s(y0), y1), y2)))
   A__FROM(first(first(cons(y0, y1), y2), y3)) -> c3(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FROM(first(first(y0, y1), 0)) -> c3(MARK(first(first(y0, y1), 0)))
   A__FROM(first(first(y0, y1), nil)) -> c3(MARK(first(first(y0, y1), nil)))
   A__FROM(first(first(y0, y1), s(y2))) -> c3(MARK(first(first(y0, y1), s(y2))))
   A__FROM(first(first(y0, y1), y2)) -> c3(MARK(first(first(y0, y1), y2)))
   A__FROM(first(from(first(y0, y1)), y2)) -> c3(MARK(first(from(first(y0, y1)), y2)))
   A__FROM(first(from(from(y0)), y1)) -> c3(MARK(first(from(from(y0)), y1)))
   A__FROM(first(from(0), y0)) -> c3(MARK(first(from(0), y0)))
   A__FROM(first(from(nil), y0)) -> c3(MARK(first(from(nil), y0)))
   A__FROM(first(from(s(y0)), y1)) -> c3(MARK(first(from(s(y0)), y1)))
   A__FROM(first(from(cons(y0, y1)), y2)) -> c3(MARK(first(from(cons(y0, y1)), y2)))
   A__FROM(first(from(y0), y1)) -> c3(MARK(first(from(y0), y1)))
   A__FROM(first(from(y0), 0)) -> c3(MARK(first(from(y0), 0)))
   A__FROM(first(from(y0), nil)) -> c3(MARK(first(from(y0), nil)))
   A__FROM(first(from(y0), s(y1))) -> c3(MARK(first(from(y0), s(y1))))
   A__FROM(first(s(first(y0, y1)), y2)) -> c3(MARK(first(s(first(y0, y1)), y2)))
   A__FROM(first(s(from(y0)), y1)) -> c3(MARK(first(s(from(y0)), y1)))
   A__FROM(first(s(0), y0)) -> c3(MARK(first(s(0), y0)))
   A__FROM(first(s(nil), y0)) -> c3(MARK(first(s(nil), y0)))
   A__FROM(first(s(s(y0)), y1)) -> c3(MARK(first(s(s(y0)), y1)))
   A__FROM(first(s(cons(y0, y1)), y2)) -> c3(MARK(first(s(cons(y0, y1)), y2)))
   A__FROM(first(s(y0), y1)) -> c3(MARK(first(s(y0), y1)))
   A__FROM(first(s(y0), 0)) -> c3(MARK(first(s(y0), 0)))
   A__FROM(first(s(y0), nil)) -> c3(MARK(first(s(y0), nil)))
   A__FROM(first(s(y0), s(y1))) -> c3(MARK(first(s(y0), s(y1))))
   A__FROM(first(0, first(y0, y1))) -> c3(MARK(first(0, first(y0, y1))))
   A__FROM(first(nil, first(y0, y1))) -> c3(MARK(first(nil, first(y0, y1))))
   A__FROM(first(0, from(y0))) -> c3(MARK(first(0, from(y0))))
   A__FROM(first(nil, from(y0))) -> c3(MARK(first(nil, from(y0))))
   A__FROM(first(y0, cons(y1, y2))) -> c3(MARK(first(y0, cons(y1, y2))))
   A__FROM(first(0, cons(y0, y1))) -> c3(MARK(first(0, cons(y0, y1))))
   A__FROM(first(nil, cons(y0, y1))) -> c3(MARK(first(nil, cons(y0, y1))))
   A__FROM(first(y0, cons(0, y1))) -> c3(MARK(first(y0, cons(0, y1))))
   A__FROM(first(y0, cons(nil, y1))) -> c3(MARK(first(y0, cons(nil, y1))))
   MARK(from(from(z0))) -> c7(A__FROM(a__from(mark(z0))), MARK(from(z0)))
   MARK(from(s(z0))) -> c7(A__FROM(s(mark(z0))), MARK(s(z0)))
   MARK(from(cons(z0, z1))) -> c7(A__FROM(cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)))
   MARK(from(first(x0, x1))) -> c7(A__FROM(first(mark(x0), mark(x1))), MARK(first(x0, x1)))
   MARK(from(first(x0, first(z0, z1)))) -> c7(A__FROM(a__first(mark(x0), a__first(mark(z0), mark(z1)))), MARK(first(x0, first(z0, z1))))
   MARK(from(first(x0, from(z0)))) -> c7(A__FROM(a__first(mark(x0), a__from(mark(z0)))), MARK(first(x0, from(z0))))
   MARK(from(first(x0, 0))) -> c7(A__FROM(a__first(mark(x0), 0)), MARK(first(x0, 0)))
   MARK(from(first(x0, nil))) -> c7(A__FROM(a__first(mark(x0), nil)), MARK(first(x0, nil)))
   MARK(from(first(x0, s(z0)))) -> c7(A__FROM(a__first(mark(x0), s(mark(z0)))), MARK(first(x0, s(z0))))
   MARK(from(first(x0, cons(z0, z1)))) -> c7(A__FROM(a__first(mark(x0), cons(mark(z0), z1))), MARK(first(x0, cons(z0, z1))))
   MARK(from(first(first(z0, z1), x1))) -> c7(A__FROM(a__first(a__first(mark(z0), mark(z1)), mark(x1))), MARK(first(first(z0, z1), x1)))
   MARK(from(first(from(z0), x1))) -> c7(A__FROM(a__first(a__from(mark(z0)), mark(x1))), MARK(first(from(z0), x1)))
   MARK(from(first(0, x1))) -> c7(A__FROM(a__first(0, mark(x1))), MARK(first(0, x1)))
   MARK(from(first(nil, x1))) -> c7(A__FROM(a__first(nil, mark(x1))), MARK(first(nil, x1)))
   MARK(from(first(s(z0), x1))) -> c7(A__FROM(a__first(s(mark(z0)), mark(x1))), MARK(first(s(z0), x1)))
   MARK(from(first(cons(z0, z1), x1))) -> c7(A__FROM(a__first(cons(mark(z0), z1), mark(x1))), MARK(first(cons(z0, z1), x1)))
S tuples:
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
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   A__FIRST(s(z0), cons(first(from(from(y0)), y1), z2)) -> c1(MARK(first(from(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(0), y0), z2)) -> c1(MARK(first(from(0), y0)))
   A__FIRST(s(z0), cons(first(from(nil), y0), z2)) -> c1(MARK(first(from(nil), y0)))
   A__FIRST(s(z0), cons(first(from(s(y0)), y1), z2)) -> c1(MARK(first(from(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(cons(y0, y1)), y2), z2)) -> c1(MARK(first(from(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(y0), y1), z2)) -> c1(MARK(first(from(y0), y1)))
   A__FIRST(s(z0), cons(first(from(y0), 0), z2)) -> c1(MARK(first(from(y0), 0)))
   A__FIRST(s(z0), cons(first(from(y0), nil), z2)) -> c1(MARK(first(from(y0), nil)))
   A__FIRST(s(z0), cons(first(from(y0), s(y1)), z2)) -> c1(MARK(first(from(y0), s(y1))))
   A__FIRST(s(z0), cons(first(s(first(y0, y1)), y2), z2)) -> c1(MARK(first(s(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(from(y0)), y1), z2)) -> c1(MARK(first(s(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(0), y0), z2)) -> c1(MARK(first(s(0), y0)))
   A__FIRST(s(z0), cons(first(s(nil), y0), z2)) -> c1(MARK(first(s(nil), y0)))
   A__FIRST(s(z0), cons(first(s(s(y0)), y1), z2)) -> c1(MARK(first(s(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(cons(y0, y1)), y2), z2)) -> c1(MARK(first(s(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(y0), y1), z2)) -> c1(MARK(first(s(y0), y1)))
   A__FIRST(s(z0), cons(first(s(y0), 0), z2)) -> c1(MARK(first(s(y0), 0)))
   A__FIRST(s(z0), cons(first(s(y0), nil), z2)) -> c1(MARK(first(s(y0), nil)))
   A__FIRST(s(z0), cons(first(s(y0), s(y1)), z2)) -> c1(MARK(first(s(y0), s(y1))))
   A__FIRST(s(z0), cons(first(0, first(y0, y1)), z2)) -> c1(MARK(first(0, first(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, first(y0, y1)), z2)) -> c1(MARK(first(nil, first(y0, y1))))
   A__FIRST(s(z0), cons(first(0, from(y0)), z2)) -> c1(MARK(first(0, from(y0))))
   A__FIRST(s(z0), cons(first(nil, from(y0)), z2)) -> c1(MARK(first(nil, from(y0))))
   A__FIRST(s(z0), cons(first(y0, cons(y1, y2)), z2)) -> c1(MARK(first(y0, cons(y1, y2))))
   A__FIRST(s(z0), cons(first(0, cons(y0, y1)), z2)) -> c1(MARK(first(0, cons(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, cons(y0, y1)), z2)) -> c1(MARK(first(nil, cons(y0, y1))))
   MARK(first(x0, cons(0, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c6(MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(MARK(cons(nil, x2)))
   A__FROM(from(y0)) -> c3(MARK(from(y0)))
   A__FROM(s(y0)) -> c3(MARK(s(y0)))
   A__FROM(cons(y0, y1)) -> c3(MARK(cons(y0, y1)))
   A__FROM(first(y0, 0)) -> c3(MARK(first(y0, 0)))
   A__FROM(first(y0, nil)) -> c3(MARK(first(y0, nil)))
   A__FROM(first(y0, s(y1))) -> c3(MARK(first(y0, s(y1))))
   A__FROM(first(cons(y0, y1), y2)) -> c3(MARK(first(cons(y0, y1), y2)))
   A__FROM(first(0, y0)) -> c3(MARK(first(0, y0)))
   A__FROM(first(nil, y0)) -> c3(MARK(first(nil, y0)))
   A__FROM(first(y0, first(y1, first(y2, y3)))) -> c3(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FROM(first(y0, first(y1, from(y2)))) -> c3(MARK(first(y0, first(y1, from(y2)))))
   A__FROM(first(y0, first(y1, 0))) -> c3(MARK(first(y0, first(y1, 0))))
   A__FROM(first(y0, first(y1, nil))) -> c3(MARK(first(y0, first(y1, nil))))
   A__FROM(first(y0, first(y1, s(y2)))) -> c3(MARK(first(y0, first(y1, s(y2)))))
   A__FROM(first(y0, first(y1, cons(y2, y3)))) -> c3(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FROM(first(y0, first(first(y1, y2), y3))) -> c3(MARK(first(y0, first(first(y1, y2), y3))))
   A__FROM(first(y0, first(from(y1), y2))) -> c3(MARK(first(y0, first(from(y1), y2))))
   A__FROM(first(y0, first(0, y1))) -> c3(MARK(first(y0, first(0, y1))))
   A__FROM(first(y0, first(nil, y1))) -> c3(MARK(first(y0, first(nil, y1))))
   A__FROM(first(y0, first(s(y1), y2))) -> c3(MARK(first(y0, first(s(y1), y2))))
   A__FROM(first(y0, first(cons(y1, y2), y3))) -> c3(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), first(y2, y3))) -> c3(MARK(first(first(y0, y1), first(y2, y3))))
   A__FROM(first(from(y0), first(y1, y2))) -> c3(MARK(first(from(y0), first(y1, y2))))
   A__FROM(first(s(y0), first(y1, y2))) -> c3(MARK(first(s(y0), first(y1, y2))))
   A__FROM(first(y0, first(y1, y2))) -> c3(MARK(first(y0, first(y1, y2))))
   A__FROM(first(cons(y0, y1), first(y2, y3))) -> c3(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FROM(first(y0, from(y1))) -> c3(MARK(first(y0, from(y1))))
   A__FROM(first(y0, from(first(y1, y2)))) -> c3(MARK(first(y0, from(first(y1, y2)))))
   A__FROM(first(y0, from(from(y1)))) -> c3(MARK(first(y0, from(from(y1)))))
   A__FROM(first(y0, from(0))) -> c3(MARK(first(y0, from(0))))
   A__FROM(first(y0, from(nil))) -> c3(MARK(first(y0, from(nil))))
   A__FROM(first(y0, from(s(y1)))) -> c3(MARK(first(y0, from(s(y1)))))
   A__FROM(first(y0, from(cons(y1, y2)))) -> c3(MARK(first(y0, from(cons(y1, y2)))))
   A__FROM(first(first(y0, y1), from(y2))) -> c3(MARK(first(first(y0, y1), from(y2))))
   A__FROM(first(from(y0), from(y1))) -> c3(MARK(first(from(y0), from(y1))))
   A__FROM(first(s(y0), from(y1))) -> c3(MARK(first(s(y0), from(y1))))
   A__FROM(first(cons(y0, y1), from(y2))) -> c3(MARK(first(cons(y0, y1), from(y2))))
   A__FROM(first(y0, cons(first(y1, y2), y3))) -> c3(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FROM(first(y0, cons(from(y1), y2))) -> c3(MARK(first(y0, cons(from(y1), y2))))
   A__FROM(first(y0, cons(s(y1), y2))) -> c3(MARK(first(y0, cons(s(y1), y2))))
   A__FROM(first(y0, cons(cons(y1, y2), y3))) -> c3(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), cons(y2, y3))) -> c3(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FROM(first(from(y0), cons(y1, y2))) -> c3(MARK(first(from(y0), cons(y1, y2))))
   A__FROM(first(s(y0), cons(y1, y2))) -> c3(MARK(first(s(y0), cons(y1, y2))))
   A__FROM(first(cons(y0, y1), cons(y2, y3))) -> c3(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FROM(first(first(y0, first(y1, y2)), y3)) -> c3(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FROM(first(first(y0, from(y1)), y2)) -> c3(MARK(first(first(y0, from(y1)), y2)))
   A__FROM(first(first(y0, 0), y1)) -> c3(MARK(first(first(y0, 0), y1)))
   A__FROM(first(first(y0, nil), y1)) -> c3(MARK(first(first(y0, nil), y1)))
   A__FROM(first(first(y0, s(y1)), y2)) -> c3(MARK(first(first(y0, s(y1)), y2)))
   A__FROM(first(first(y0, cons(y1, y2)), y3)) -> c3(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FROM(first(first(first(y0, y1), y2), y3)) -> c3(MARK(first(first(first(y0, y1), y2), y3)))
   A__FROM(first(first(from(y0), y1), y2)) -> c3(MARK(first(first(from(y0), y1), y2)))
   A__FROM(first(first(0, y0), y1)) -> c3(MARK(first(first(0, y0), y1)))
   A__FROM(first(first(nil, y0), y1)) -> c3(MARK(first(first(nil, y0), y1)))
   A__FROM(first(first(s(y0), y1), y2)) -> c3(MARK(first(first(s(y0), y1), y2)))
   A__FROM(first(first(cons(y0, y1), y2), y3)) -> c3(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FROM(first(first(y0, y1), 0)) -> c3(MARK(first(first(y0, y1), 0)))
   A__FROM(first(first(y0, y1), nil)) -> c3(MARK(first(first(y0, y1), nil)))
   A__FROM(first(first(y0, y1), s(y2))) -> c3(MARK(first(first(y0, y1), s(y2))))
   A__FROM(first(first(y0, y1), y2)) -> c3(MARK(first(first(y0, y1), y2)))
   A__FROM(first(from(first(y0, y1)), y2)) -> c3(MARK(first(from(first(y0, y1)), y2)))
   A__FROM(first(from(from(y0)), y1)) -> c3(MARK(first(from(from(y0)), y1)))
   A__FROM(first(from(0), y0)) -> c3(MARK(first(from(0), y0)))
   A__FROM(first(from(nil), y0)) -> c3(MARK(first(from(nil), y0)))
   A__FROM(first(from(s(y0)), y1)) -> c3(MARK(first(from(s(y0)), y1)))
   A__FROM(first(from(cons(y0, y1)), y2)) -> c3(MARK(first(from(cons(y0, y1)), y2)))
   A__FROM(first(from(y0), y1)) -> c3(MARK(first(from(y0), y1)))
   A__FROM(first(from(y0), 0)) -> c3(MARK(first(from(y0), 0)))
   A__FROM(first(from(y0), nil)) -> c3(MARK(first(from(y0), nil)))
   A__FROM(first(from(y0), s(y1))) -> c3(MARK(first(from(y0), s(y1))))
   A__FROM(first(s(first(y0, y1)), y2)) -> c3(MARK(first(s(first(y0, y1)), y2)))
   A__FROM(first(s(from(y0)), y1)) -> c3(MARK(first(s(from(y0)), y1)))
   A__FROM(first(s(0), y0)) -> c3(MARK(first(s(0), y0)))
   A__FROM(first(s(nil), y0)) -> c3(MARK(first(s(nil), y0)))
   A__FROM(first(s(s(y0)), y1)) -> c3(MARK(first(s(s(y0)), y1)))
   A__FROM(first(s(cons(y0, y1)), y2)) -> c3(MARK(first(s(cons(y0, y1)), y2)))
   A__FROM(first(s(y0), y1)) -> c3(MARK(first(s(y0), y1)))
   A__FROM(first(s(y0), 0)) -> c3(MARK(first(s(y0), 0)))
   A__FROM(first(s(y0), nil)) -> c3(MARK(first(s(y0), nil)))
   A__FROM(first(s(y0), s(y1))) -> c3(MARK(first(s(y0), s(y1))))
   A__FROM(first(0, first(y0, y1))) -> c3(MARK(first(0, first(y0, y1))))
   A__FROM(first(nil, first(y0, y1))) -> c3(MARK(first(nil, first(y0, y1))))
   A__FROM(first(0, from(y0))) -> c3(MARK(first(0, from(y0))))
   A__FROM(first(nil, from(y0))) -> c3(MARK(first(nil, from(y0))))
   A__FROM(first(y0, cons(y1, y2))) -> c3(MARK(first(y0, cons(y1, y2))))
   A__FROM(first(0, cons(y0, y1))) -> c3(MARK(first(0, cons(y0, y1))))
   A__FROM(first(nil, cons(y0, y1))) -> c3(MARK(first(nil, cons(y0, y1))))
   A__FROM(first(y0, cons(0, y1))) -> c3(MARK(first(y0, cons(0, y1))))
   A__FROM(first(y0, cons(nil, y1))) -> c3(MARK(first(y0, cons(nil, y1))))
   MARK(from(from(z0))) -> c7(A__FROM(a__from(mark(z0))), MARK(from(z0)))
   MARK(from(s(z0))) -> c7(A__FROM(s(mark(z0))), MARK(s(z0)))
   MARK(from(cons(z0, z1))) -> c7(A__FROM(cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)))
   MARK(from(first(x0, x1))) -> c7(A__FROM(first(mark(x0), mark(x1))), MARK(first(x0, x1)))
   MARK(from(first(x0, first(z0, z1)))) -> c7(A__FROM(a__first(mark(x0), a__first(mark(z0), mark(z1)))), MARK(first(x0, first(z0, z1))))
   MARK(from(first(x0, from(z0)))) -> c7(A__FROM(a__first(mark(x0), a__from(mark(z0)))), MARK(first(x0, from(z0))))
   MARK(from(first(x0, 0))) -> c7(A__FROM(a__first(mark(x0), 0)), MARK(first(x0, 0)))
   MARK(from(first(x0, nil))) -> c7(A__FROM(a__first(mark(x0), nil)), MARK(first(x0, nil)))
   MARK(from(first(x0, s(z0)))) -> c7(A__FROM(a__first(mark(x0), s(mark(z0)))), MARK(first(x0, s(z0))))
   MARK(from(first(x0, cons(z0, z1)))) -> c7(A__FROM(a__first(mark(x0), cons(mark(z0), z1))), MARK(first(x0, cons(z0, z1))))
   MARK(from(first(first(z0, z1), x1))) -> c7(A__FROM(a__first(a__first(mark(z0), mark(z1)), mark(x1))), MARK(first(first(z0, z1), x1)))
   MARK(from(first(from(z0), x1))) -> c7(A__FROM(a__first(a__from(mark(z0)), mark(x1))), MARK(first(from(z0), x1)))
   MARK(from(first(0, x1))) -> c7(A__FROM(a__first(0, mark(x1))), MARK(first(0, x1)))
   MARK(from(first(nil, x1))) -> c7(A__FROM(a__first(nil, mark(x1))), MARK(first(nil, x1)))
   MARK(from(first(s(z0), x1))) -> c7(A__FROM(a__first(s(mark(z0)), mark(x1))), MARK(first(s(z0), x1)))
   MARK(from(first(cons(z0, z1), x1))) -> c7(A__FROM(a__first(cons(mark(z0), z1), mark(x1))), MARK(first(cons(z0, z1), x1)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   MARK_1, A__FIRST_2, A__FROM_1

Compound Symbols:   c10_1, c11_1, c5_1, c6_1, c5_2, c6_2, c1_1, c3_1, c7_2


----------------------------------------

(111) CdtNarrowingProof (BOTH BOUNDS(ID, ID))
Use narrowing to replace MARK(from(from(z0))) -> c7(A__FROM(a__from(mark(z0))), MARK(from(z0))) by 
   MARK(from(from(x0))) -> c7(A__FROM(cons(mark(mark(x0)), from(s(mark(x0))))), MARK(from(x0)))
   MARK(from(from(x0))) -> c7(A__FROM(from(mark(x0))), MARK(from(x0)))
   MARK(from(from(first(z0, z1)))) -> c7(A__FROM(a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(from(from(from(z0)))) -> c7(A__FROM(a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(from(from(0))) -> c7(A__FROM(a__from(0)), MARK(from(0)))
   MARK(from(from(nil))) -> c7(A__FROM(a__from(nil)), MARK(from(nil)))
   MARK(from(from(s(z0)))) -> c7(A__FROM(a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(from(from(cons(z0, z1)))) -> c7(A__FROM(a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))

----------------------------------------

(112)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
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   A__FIRST(s(z0), cons(first(first(y0, s(y1)), y2), z2)) -> c1(MARK(first(first(y0, s(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, cons(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(first(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(first(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(from(y0), y1), y2), z2)) -> c1(MARK(first(first(from(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(0, y0), y1), z2)) -> c1(MARK(first(first(0, y0), y1)))
   A__FIRST(s(z0), cons(first(first(nil, y0), y1), z2)) -> c1(MARK(first(first(nil, y0), y1)))
   A__FIRST(s(z0), cons(first(first(s(y0), y1), y2), z2)) -> c1(MARK(first(first(s(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(cons(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(y0, y1), 0), z2)) -> c1(MARK(first(first(y0, y1), 0)))
   A__FIRST(s(z0), cons(first(first(y0, y1), nil), z2)) -> c1(MARK(first(first(y0, y1), nil)))
   A__FIRST(s(z0), cons(first(first(y0, y1), s(y2)), z2)) -> c1(MARK(first(first(y0, y1), s(y2))))
   A__FIRST(s(z0), cons(first(first(y0, y1), y2), z2)) -> c1(MARK(first(first(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(from(first(y0, y1)), y2), z2)) -> c1(MARK(first(from(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(from(y0)), y1), z2)) -> c1(MARK(first(from(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(0), y0), z2)) -> c1(MARK(first(from(0), y0)))
   A__FIRST(s(z0), cons(first(from(nil), y0), z2)) -> c1(MARK(first(from(nil), y0)))
   A__FIRST(s(z0), cons(first(from(s(y0)), y1), z2)) -> c1(MARK(first(from(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(cons(y0, y1)), y2), z2)) -> c1(MARK(first(from(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(y0), y1), z2)) -> c1(MARK(first(from(y0), y1)))
   A__FIRST(s(z0), cons(first(from(y0), 0), z2)) -> c1(MARK(first(from(y0), 0)))
   A__FIRST(s(z0), cons(first(from(y0), nil), z2)) -> c1(MARK(first(from(y0), nil)))
   A__FIRST(s(z0), cons(first(from(y0), s(y1)), z2)) -> c1(MARK(first(from(y0), s(y1))))
   A__FIRST(s(z0), cons(first(s(first(y0, y1)), y2), z2)) -> c1(MARK(first(s(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(from(y0)), y1), z2)) -> c1(MARK(first(s(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(0), y0), z2)) -> c1(MARK(first(s(0), y0)))
   A__FIRST(s(z0), cons(first(s(nil), y0), z2)) -> c1(MARK(first(s(nil), y0)))
   A__FIRST(s(z0), cons(first(s(s(y0)), y1), z2)) -> c1(MARK(first(s(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(cons(y0, y1)), y2), z2)) -> c1(MARK(first(s(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(y0), y1), z2)) -> c1(MARK(first(s(y0), y1)))
   A__FIRST(s(z0), cons(first(s(y0), 0), z2)) -> c1(MARK(first(s(y0), 0)))
   A__FIRST(s(z0), cons(first(s(y0), nil), z2)) -> c1(MARK(first(s(y0), nil)))
   A__FIRST(s(z0), cons(first(s(y0), s(y1)), z2)) -> c1(MARK(first(s(y0), s(y1))))
   A__FIRST(s(z0), cons(first(0, first(y0, y1)), z2)) -> c1(MARK(first(0, first(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, first(y0, y1)), z2)) -> c1(MARK(first(nil, first(y0, y1))))
   A__FIRST(s(z0), cons(first(0, from(y0)), z2)) -> c1(MARK(first(0, from(y0))))
   A__FIRST(s(z0), cons(first(nil, from(y0)), z2)) -> c1(MARK(first(nil, from(y0))))
   A__FIRST(s(z0), cons(first(y0, cons(y1, y2)), z2)) -> c1(MARK(first(y0, cons(y1, y2))))
   A__FIRST(s(z0), cons(first(0, cons(y0, y1)), z2)) -> c1(MARK(first(0, cons(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, cons(y0, y1)), z2)) -> c1(MARK(first(nil, cons(y0, y1))))
   MARK(first(x0, cons(0, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c6(MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(MARK(cons(nil, x2)))
   A__FROM(from(y0)) -> c3(MARK(from(y0)))
   A__FROM(s(y0)) -> c3(MARK(s(y0)))
   A__FROM(cons(y0, y1)) -> c3(MARK(cons(y0, y1)))
   A__FROM(first(y0, 0)) -> c3(MARK(first(y0, 0)))
   A__FROM(first(y0, nil)) -> c3(MARK(first(y0, nil)))
   A__FROM(first(y0, s(y1))) -> c3(MARK(first(y0, s(y1))))
   A__FROM(first(cons(y0, y1), y2)) -> c3(MARK(first(cons(y0, y1), y2)))
   A__FROM(first(0, y0)) -> c3(MARK(first(0, y0)))
   A__FROM(first(nil, y0)) -> c3(MARK(first(nil, y0)))
   A__FROM(first(y0, first(y1, first(y2, y3)))) -> c3(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FROM(first(y0, first(y1, from(y2)))) -> c3(MARK(first(y0, first(y1, from(y2)))))
   A__FROM(first(y0, first(y1, 0))) -> c3(MARK(first(y0, first(y1, 0))))
   A__FROM(first(y0, first(y1, nil))) -> c3(MARK(first(y0, first(y1, nil))))
   A__FROM(first(y0, first(y1, s(y2)))) -> c3(MARK(first(y0, first(y1, s(y2)))))
   A__FROM(first(y0, first(y1, cons(y2, y3)))) -> c3(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FROM(first(y0, first(first(y1, y2), y3))) -> c3(MARK(first(y0, first(first(y1, y2), y3))))
   A__FROM(first(y0, first(from(y1), y2))) -> c3(MARK(first(y0, first(from(y1), y2))))
   A__FROM(first(y0, first(0, y1))) -> c3(MARK(first(y0, first(0, y1))))
   A__FROM(first(y0, first(nil, y1))) -> c3(MARK(first(y0, first(nil, y1))))
   A__FROM(first(y0, first(s(y1), y2))) -> c3(MARK(first(y0, first(s(y1), y2))))
   A__FROM(first(y0, first(cons(y1, y2), y3))) -> c3(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), first(y2, y3))) -> c3(MARK(first(first(y0, y1), first(y2, y3))))
   A__FROM(first(from(y0), first(y1, y2))) -> c3(MARK(first(from(y0), first(y1, y2))))
   A__FROM(first(s(y0), first(y1, y2))) -> c3(MARK(first(s(y0), first(y1, y2))))
   A__FROM(first(y0, first(y1, y2))) -> c3(MARK(first(y0, first(y1, y2))))
   A__FROM(first(cons(y0, y1), first(y2, y3))) -> c3(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FROM(first(y0, from(y1))) -> c3(MARK(first(y0, from(y1))))
   A__FROM(first(y0, from(first(y1, y2)))) -> c3(MARK(first(y0, from(first(y1, y2)))))
   A__FROM(first(y0, from(from(y1)))) -> c3(MARK(first(y0, from(from(y1)))))
   A__FROM(first(y0, from(0))) -> c3(MARK(first(y0, from(0))))
   A__FROM(first(y0, from(nil))) -> c3(MARK(first(y0, from(nil))))
   A__FROM(first(y0, from(s(y1)))) -> c3(MARK(first(y0, from(s(y1)))))
   A__FROM(first(y0, from(cons(y1, y2)))) -> c3(MARK(first(y0, from(cons(y1, y2)))))
   A__FROM(first(first(y0, y1), from(y2))) -> c3(MARK(first(first(y0, y1), from(y2))))
   A__FROM(first(from(y0), from(y1))) -> c3(MARK(first(from(y0), from(y1))))
   A__FROM(first(s(y0), from(y1))) -> c3(MARK(first(s(y0), from(y1))))
   A__FROM(first(cons(y0, y1), from(y2))) -> c3(MARK(first(cons(y0, y1), from(y2))))
   A__FROM(first(y0, cons(first(y1, y2), y3))) -> c3(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FROM(first(y0, cons(from(y1), y2))) -> c3(MARK(first(y0, cons(from(y1), y2))))
   A__FROM(first(y0, cons(s(y1), y2))) -> c3(MARK(first(y0, cons(s(y1), y2))))
   A__FROM(first(y0, cons(cons(y1, y2), y3))) -> c3(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), cons(y2, y3))) -> c3(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FROM(first(from(y0), cons(y1, y2))) -> c3(MARK(first(from(y0), cons(y1, y2))))
   A__FROM(first(s(y0), cons(y1, y2))) -> c3(MARK(first(s(y0), cons(y1, y2))))
   A__FROM(first(cons(y0, y1), cons(y2, y3))) -> c3(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FROM(first(first(y0, first(y1, y2)), y3)) -> c3(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FROM(first(first(y0, from(y1)), y2)) -> c3(MARK(first(first(y0, from(y1)), y2)))
   A__FROM(first(first(y0, 0), y1)) -> c3(MARK(first(first(y0, 0), y1)))
   A__FROM(first(first(y0, nil), y1)) -> c3(MARK(first(first(y0, nil), y1)))
   A__FROM(first(first(y0, s(y1)), y2)) -> c3(MARK(first(first(y0, s(y1)), y2)))
   A__FROM(first(first(y0, cons(y1, y2)), y3)) -> c3(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FROM(first(first(first(y0, y1), y2), y3)) -> c3(MARK(first(first(first(y0, y1), y2), y3)))
   A__FROM(first(first(from(y0), y1), y2)) -> c3(MARK(first(first(from(y0), y1), y2)))
   A__FROM(first(first(0, y0), y1)) -> c3(MARK(first(first(0, y0), y1)))
   A__FROM(first(first(nil, y0), y1)) -> c3(MARK(first(first(nil, y0), y1)))
   A__FROM(first(first(s(y0), y1), y2)) -> c3(MARK(first(first(s(y0), y1), y2)))
   A__FROM(first(first(cons(y0, y1), y2), y3)) -> c3(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FROM(first(first(y0, y1), 0)) -> c3(MARK(first(first(y0, y1), 0)))
   A__FROM(first(first(y0, y1), nil)) -> c3(MARK(first(first(y0, y1), nil)))
   A__FROM(first(first(y0, y1), s(y2))) -> c3(MARK(first(first(y0, y1), s(y2))))
   A__FROM(first(first(y0, y1), y2)) -> c3(MARK(first(first(y0, y1), y2)))
   A__FROM(first(from(first(y0, y1)), y2)) -> c3(MARK(first(from(first(y0, y1)), y2)))
   A__FROM(first(from(from(y0)), y1)) -> c3(MARK(first(from(from(y0)), y1)))
   A__FROM(first(from(0), y0)) -> c3(MARK(first(from(0), y0)))
   A__FROM(first(from(nil), y0)) -> c3(MARK(first(from(nil), y0)))
   A__FROM(first(from(s(y0)), y1)) -> c3(MARK(first(from(s(y0)), y1)))
   A__FROM(first(from(cons(y0, y1)), y2)) -> c3(MARK(first(from(cons(y0, y1)), y2)))
   A__FROM(first(from(y0), y1)) -> c3(MARK(first(from(y0), y1)))
   A__FROM(first(from(y0), 0)) -> c3(MARK(first(from(y0), 0)))
   A__FROM(first(from(y0), nil)) -> c3(MARK(first(from(y0), nil)))
   A__FROM(first(from(y0), s(y1))) -> c3(MARK(first(from(y0), s(y1))))
   A__FROM(first(s(first(y0, y1)), y2)) -> c3(MARK(first(s(first(y0, y1)), y2)))
   A__FROM(first(s(from(y0)), y1)) -> c3(MARK(first(s(from(y0)), y1)))
   A__FROM(first(s(0), y0)) -> c3(MARK(first(s(0), y0)))
   A__FROM(first(s(nil), y0)) -> c3(MARK(first(s(nil), y0)))
   A__FROM(first(s(s(y0)), y1)) -> c3(MARK(first(s(s(y0)), y1)))
   A__FROM(first(s(cons(y0, y1)), y2)) -> c3(MARK(first(s(cons(y0, y1)), y2)))
   A__FROM(first(s(y0), y1)) -> c3(MARK(first(s(y0), y1)))
   A__FROM(first(s(y0), 0)) -> c3(MARK(first(s(y0), 0)))
   A__FROM(first(s(y0), nil)) -> c3(MARK(first(s(y0), nil)))
   A__FROM(first(s(y0), s(y1))) -> c3(MARK(first(s(y0), s(y1))))
   A__FROM(first(0, first(y0, y1))) -> c3(MARK(first(0, first(y0, y1))))
   A__FROM(first(nil, first(y0, y1))) -> c3(MARK(first(nil, first(y0, y1))))
   A__FROM(first(0, from(y0))) -> c3(MARK(first(0, from(y0))))
   A__FROM(first(nil, from(y0))) -> c3(MARK(first(nil, from(y0))))
   A__FROM(first(y0, cons(y1, y2))) -> c3(MARK(first(y0, cons(y1, y2))))
   A__FROM(first(0, cons(y0, y1))) -> c3(MARK(first(0, cons(y0, y1))))
   A__FROM(first(nil, cons(y0, y1))) -> c3(MARK(first(nil, cons(y0, y1))))
   A__FROM(first(y0, cons(0, y1))) -> c3(MARK(first(y0, cons(0, y1))))
   A__FROM(first(y0, cons(nil, y1))) -> c3(MARK(first(y0, cons(nil, y1))))
   MARK(from(s(z0))) -> c7(A__FROM(s(mark(z0))), MARK(s(z0)))
   MARK(from(cons(z0, z1))) -> c7(A__FROM(cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)))
   MARK(from(first(x0, x1))) -> c7(A__FROM(first(mark(x0), mark(x1))), MARK(first(x0, x1)))
   MARK(from(first(x0, first(z0, z1)))) -> c7(A__FROM(a__first(mark(x0), a__first(mark(z0), mark(z1)))), MARK(first(x0, first(z0, z1))))
   MARK(from(first(x0, from(z0)))) -> c7(A__FROM(a__first(mark(x0), a__from(mark(z0)))), MARK(first(x0, from(z0))))
   MARK(from(first(x0, 0))) -> c7(A__FROM(a__first(mark(x0), 0)), MARK(first(x0, 0)))
   MARK(from(first(x0, nil))) -> c7(A__FROM(a__first(mark(x0), nil)), MARK(first(x0, nil)))
   MARK(from(first(x0, s(z0)))) -> c7(A__FROM(a__first(mark(x0), s(mark(z0)))), MARK(first(x0, s(z0))))
   MARK(from(first(x0, cons(z0, z1)))) -> c7(A__FROM(a__first(mark(x0), cons(mark(z0), z1))), MARK(first(x0, cons(z0, z1))))
   MARK(from(first(first(z0, z1), x1))) -> c7(A__FROM(a__first(a__first(mark(z0), mark(z1)), mark(x1))), MARK(first(first(z0, z1), x1)))
   MARK(from(first(from(z0), x1))) -> c7(A__FROM(a__first(a__from(mark(z0)), mark(x1))), MARK(first(from(z0), x1)))
   MARK(from(first(0, x1))) -> c7(A__FROM(a__first(0, mark(x1))), MARK(first(0, x1)))
   MARK(from(first(nil, x1))) -> c7(A__FROM(a__first(nil, mark(x1))), MARK(first(nil, x1)))
   MARK(from(first(s(z0), x1))) -> c7(A__FROM(a__first(s(mark(z0)), mark(x1))), MARK(first(s(z0), x1)))
   MARK(from(first(cons(z0, z1), x1))) -> c7(A__FROM(a__first(cons(mark(z0), z1), mark(x1))), MARK(first(cons(z0, z1), x1)))
   MARK(from(from(x0))) -> c7(A__FROM(cons(mark(mark(x0)), from(s(mark(x0))))), MARK(from(x0)))
   MARK(from(from(x0))) -> c7(A__FROM(from(mark(x0))), MARK(from(x0)))
   MARK(from(from(first(z0, z1)))) -> c7(A__FROM(a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(from(from(from(z0)))) -> c7(A__FROM(a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(from(from(0))) -> c7(A__FROM(a__from(0)), MARK(from(0)))
   MARK(from(from(nil))) -> c7(A__FROM(a__from(nil)), MARK(from(nil)))
   MARK(from(from(s(z0)))) -> c7(A__FROM(a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(from(from(cons(z0, z1)))) -> c7(A__FROM(a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
S tuples:
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
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   A__FIRST(s(z0), cons(first(first(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), cons(y1, y2)), z2)) -> c1(MARK(first(from(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), cons(y1, y2)), z2)) -> c1(MARK(first(s(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(first(y0, first(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(y0, from(y1)), y2), z2)) -> c1(MARK(first(first(y0, from(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, 0), y1), z2)) -> c1(MARK(first(first(y0, 0), y1)))
   A__FIRST(s(z0), cons(first(first(y0, nil), y1), z2)) -> c1(MARK(first(first(y0, nil), y1)))
   A__FIRST(s(z0), cons(first(first(y0, s(y1)), y2), z2)) -> c1(MARK(first(first(y0, s(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, cons(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(first(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(first(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(from(y0), y1), y2), z2)) -> c1(MARK(first(first(from(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(0, y0), y1), z2)) -> c1(MARK(first(first(0, y0), y1)))
   A__FIRST(s(z0), cons(first(first(nil, y0), y1), z2)) -> c1(MARK(first(first(nil, y0), y1)))
   A__FIRST(s(z0), cons(first(first(s(y0), y1), y2), z2)) -> c1(MARK(first(first(s(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(cons(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(y0, y1), 0), z2)) -> c1(MARK(first(first(y0, y1), 0)))
   A__FIRST(s(z0), cons(first(first(y0, y1), nil), z2)) -> c1(MARK(first(first(y0, y1), nil)))
   A__FIRST(s(z0), cons(first(first(y0, y1), s(y2)), z2)) -> c1(MARK(first(first(y0, y1), s(y2))))
   A__FIRST(s(z0), cons(first(first(y0, y1), y2), z2)) -> c1(MARK(first(first(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(from(first(y0, y1)), y2), z2)) -> c1(MARK(first(from(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(from(y0)), y1), z2)) -> c1(MARK(first(from(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(0), y0), z2)) -> c1(MARK(first(from(0), y0)))
   A__FIRST(s(z0), cons(first(from(nil), y0), z2)) -> c1(MARK(first(from(nil), y0)))
   A__FIRST(s(z0), cons(first(from(s(y0)), y1), z2)) -> c1(MARK(first(from(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(cons(y0, y1)), y2), z2)) -> c1(MARK(first(from(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(y0), y1), z2)) -> c1(MARK(first(from(y0), y1)))
   A__FIRST(s(z0), cons(first(from(y0), 0), z2)) -> c1(MARK(first(from(y0), 0)))
   A__FIRST(s(z0), cons(first(from(y0), nil), z2)) -> c1(MARK(first(from(y0), nil)))
   A__FIRST(s(z0), cons(first(from(y0), s(y1)), z2)) -> c1(MARK(first(from(y0), s(y1))))
   A__FIRST(s(z0), cons(first(s(first(y0, y1)), y2), z2)) -> c1(MARK(first(s(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(from(y0)), y1), z2)) -> c1(MARK(first(s(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(0), y0), z2)) -> c1(MARK(first(s(0), y0)))
   A__FIRST(s(z0), cons(first(s(nil), y0), z2)) -> c1(MARK(first(s(nil), y0)))
   A__FIRST(s(z0), cons(first(s(s(y0)), y1), z2)) -> c1(MARK(first(s(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(cons(y0, y1)), y2), z2)) -> c1(MARK(first(s(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(y0), y1), z2)) -> c1(MARK(first(s(y0), y1)))
   A__FIRST(s(z0), cons(first(s(y0), 0), z2)) -> c1(MARK(first(s(y0), 0)))
   A__FIRST(s(z0), cons(first(s(y0), nil), z2)) -> c1(MARK(first(s(y0), nil)))
   A__FIRST(s(z0), cons(first(s(y0), s(y1)), z2)) -> c1(MARK(first(s(y0), s(y1))))
   A__FIRST(s(z0), cons(first(0, first(y0, y1)), z2)) -> c1(MARK(first(0, first(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, first(y0, y1)), z2)) -> c1(MARK(first(nil, first(y0, y1))))
   A__FIRST(s(z0), cons(first(0, from(y0)), z2)) -> c1(MARK(first(0, from(y0))))
   A__FIRST(s(z0), cons(first(nil, from(y0)), z2)) -> c1(MARK(first(nil, from(y0))))
   A__FIRST(s(z0), cons(first(y0, cons(y1, y2)), z2)) -> c1(MARK(first(y0, cons(y1, y2))))
   A__FIRST(s(z0), cons(first(0, cons(y0, y1)), z2)) -> c1(MARK(first(0, cons(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, cons(y0, y1)), z2)) -> c1(MARK(first(nil, cons(y0, y1))))
   MARK(first(x0, cons(0, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c6(MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(MARK(cons(nil, x2)))
   A__FROM(from(y0)) -> c3(MARK(from(y0)))
   A__FROM(s(y0)) -> c3(MARK(s(y0)))
   A__FROM(cons(y0, y1)) -> c3(MARK(cons(y0, y1)))
   A__FROM(first(y0, 0)) -> c3(MARK(first(y0, 0)))
   A__FROM(first(y0, nil)) -> c3(MARK(first(y0, nil)))
   A__FROM(first(y0, s(y1))) -> c3(MARK(first(y0, s(y1))))
   A__FROM(first(cons(y0, y1), y2)) -> c3(MARK(first(cons(y0, y1), y2)))
   A__FROM(first(0, y0)) -> c3(MARK(first(0, y0)))
   A__FROM(first(nil, y0)) -> c3(MARK(first(nil, y0)))
   A__FROM(first(y0, first(y1, first(y2, y3)))) -> c3(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FROM(first(y0, first(y1, from(y2)))) -> c3(MARK(first(y0, first(y1, from(y2)))))
   A__FROM(first(y0, first(y1, 0))) -> c3(MARK(first(y0, first(y1, 0))))
   A__FROM(first(y0, first(y1, nil))) -> c3(MARK(first(y0, first(y1, nil))))
   A__FROM(first(y0, first(y1, s(y2)))) -> c3(MARK(first(y0, first(y1, s(y2)))))
   A__FROM(first(y0, first(y1, cons(y2, y3)))) -> c3(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FROM(first(y0, first(first(y1, y2), y3))) -> c3(MARK(first(y0, first(first(y1, y2), y3))))
   A__FROM(first(y0, first(from(y1), y2))) -> c3(MARK(first(y0, first(from(y1), y2))))
   A__FROM(first(y0, first(0, y1))) -> c3(MARK(first(y0, first(0, y1))))
   A__FROM(first(y0, first(nil, y1))) -> c3(MARK(first(y0, first(nil, y1))))
   A__FROM(first(y0, first(s(y1), y2))) -> c3(MARK(first(y0, first(s(y1), y2))))
   A__FROM(first(y0, first(cons(y1, y2), y3))) -> c3(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), first(y2, y3))) -> c3(MARK(first(first(y0, y1), first(y2, y3))))
   A__FROM(first(from(y0), first(y1, y2))) -> c3(MARK(first(from(y0), first(y1, y2))))
   A__FROM(first(s(y0), first(y1, y2))) -> c3(MARK(first(s(y0), first(y1, y2))))
   A__FROM(first(y0, first(y1, y2))) -> c3(MARK(first(y0, first(y1, y2))))
   A__FROM(first(cons(y0, y1), first(y2, y3))) -> c3(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FROM(first(y0, from(y1))) -> c3(MARK(first(y0, from(y1))))
   A__FROM(first(y0, from(first(y1, y2)))) -> c3(MARK(first(y0, from(first(y1, y2)))))
   A__FROM(first(y0, from(from(y1)))) -> c3(MARK(first(y0, from(from(y1)))))
   A__FROM(first(y0, from(0))) -> c3(MARK(first(y0, from(0))))
   A__FROM(first(y0, from(nil))) -> c3(MARK(first(y0, from(nil))))
   A__FROM(first(y0, from(s(y1)))) -> c3(MARK(first(y0, from(s(y1)))))
   A__FROM(first(y0, from(cons(y1, y2)))) -> c3(MARK(first(y0, from(cons(y1, y2)))))
   A__FROM(first(first(y0, y1), from(y2))) -> c3(MARK(first(first(y0, y1), from(y2))))
   A__FROM(first(from(y0), from(y1))) -> c3(MARK(first(from(y0), from(y1))))
   A__FROM(first(s(y0), from(y1))) -> c3(MARK(first(s(y0), from(y1))))
   A__FROM(first(cons(y0, y1), from(y2))) -> c3(MARK(first(cons(y0, y1), from(y2))))
   A__FROM(first(y0, cons(first(y1, y2), y3))) -> c3(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FROM(first(y0, cons(from(y1), y2))) -> c3(MARK(first(y0, cons(from(y1), y2))))
   A__FROM(first(y0, cons(s(y1), y2))) -> c3(MARK(first(y0, cons(s(y1), y2))))
   A__FROM(first(y0, cons(cons(y1, y2), y3))) -> c3(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), cons(y2, y3))) -> c3(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FROM(first(from(y0), cons(y1, y2))) -> c3(MARK(first(from(y0), cons(y1, y2))))
   A__FROM(first(s(y0), cons(y1, y2))) -> c3(MARK(first(s(y0), cons(y1, y2))))
   A__FROM(first(cons(y0, y1), cons(y2, y3))) -> c3(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FROM(first(first(y0, first(y1, y2)), y3)) -> c3(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FROM(first(first(y0, from(y1)), y2)) -> c3(MARK(first(first(y0, from(y1)), y2)))
   A__FROM(first(first(y0, 0), y1)) -> c3(MARK(first(first(y0, 0), y1)))
   A__FROM(first(first(y0, nil), y1)) -> c3(MARK(first(first(y0, nil), y1)))
   A__FROM(first(first(y0, s(y1)), y2)) -> c3(MARK(first(first(y0, s(y1)), y2)))
   A__FROM(first(first(y0, cons(y1, y2)), y3)) -> c3(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FROM(first(first(first(y0, y1), y2), y3)) -> c3(MARK(first(first(first(y0, y1), y2), y3)))
   A__FROM(first(first(from(y0), y1), y2)) -> c3(MARK(first(first(from(y0), y1), y2)))
   A__FROM(first(first(0, y0), y1)) -> c3(MARK(first(first(0, y0), y1)))
   A__FROM(first(first(nil, y0), y1)) -> c3(MARK(first(first(nil, y0), y1)))
   A__FROM(first(first(s(y0), y1), y2)) -> c3(MARK(first(first(s(y0), y1), y2)))
   A__FROM(first(first(cons(y0, y1), y2), y3)) -> c3(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FROM(first(first(y0, y1), 0)) -> c3(MARK(first(first(y0, y1), 0)))
   A__FROM(first(first(y0, y1), nil)) -> c3(MARK(first(first(y0, y1), nil)))
   A__FROM(first(first(y0, y1), s(y2))) -> c3(MARK(first(first(y0, y1), s(y2))))
   A__FROM(first(first(y0, y1), y2)) -> c3(MARK(first(first(y0, y1), y2)))
   A__FROM(first(from(first(y0, y1)), y2)) -> c3(MARK(first(from(first(y0, y1)), y2)))
   A__FROM(first(from(from(y0)), y1)) -> c3(MARK(first(from(from(y0)), y1)))
   A__FROM(first(from(0), y0)) -> c3(MARK(first(from(0), y0)))
   A__FROM(first(from(nil), y0)) -> c3(MARK(first(from(nil), y0)))
   A__FROM(first(from(s(y0)), y1)) -> c3(MARK(first(from(s(y0)), y1)))
   A__FROM(first(from(cons(y0, y1)), y2)) -> c3(MARK(first(from(cons(y0, y1)), y2)))
   A__FROM(first(from(y0), y1)) -> c3(MARK(first(from(y0), y1)))
   A__FROM(first(from(y0), 0)) -> c3(MARK(first(from(y0), 0)))
   A__FROM(first(from(y0), nil)) -> c3(MARK(first(from(y0), nil)))
   A__FROM(first(from(y0), s(y1))) -> c3(MARK(first(from(y0), s(y1))))
   A__FROM(first(s(first(y0, y1)), y2)) -> c3(MARK(first(s(first(y0, y1)), y2)))
   A__FROM(first(s(from(y0)), y1)) -> c3(MARK(first(s(from(y0)), y1)))
   A__FROM(first(s(0), y0)) -> c3(MARK(first(s(0), y0)))
   A__FROM(first(s(nil), y0)) -> c3(MARK(first(s(nil), y0)))
   A__FROM(first(s(s(y0)), y1)) -> c3(MARK(first(s(s(y0)), y1)))
   A__FROM(first(s(cons(y0, y1)), y2)) -> c3(MARK(first(s(cons(y0, y1)), y2)))
   A__FROM(first(s(y0), y1)) -> c3(MARK(first(s(y0), y1)))
   A__FROM(first(s(y0), 0)) -> c3(MARK(first(s(y0), 0)))
   A__FROM(first(s(y0), nil)) -> c3(MARK(first(s(y0), nil)))
   A__FROM(first(s(y0), s(y1))) -> c3(MARK(first(s(y0), s(y1))))
   A__FROM(first(0, first(y0, y1))) -> c3(MARK(first(0, first(y0, y1))))
   A__FROM(first(nil, first(y0, y1))) -> c3(MARK(first(nil, first(y0, y1))))
   A__FROM(first(0, from(y0))) -> c3(MARK(first(0, from(y0))))
   A__FROM(first(nil, from(y0))) -> c3(MARK(first(nil, from(y0))))
   A__FROM(first(y0, cons(y1, y2))) -> c3(MARK(first(y0, cons(y1, y2))))
   A__FROM(first(0, cons(y0, y1))) -> c3(MARK(first(0, cons(y0, y1))))
   A__FROM(first(nil, cons(y0, y1))) -> c3(MARK(first(nil, cons(y0, y1))))
   A__FROM(first(y0, cons(0, y1))) -> c3(MARK(first(y0, cons(0, y1))))
   A__FROM(first(y0, cons(nil, y1))) -> c3(MARK(first(y0, cons(nil, y1))))
   MARK(from(s(z0))) -> c7(A__FROM(s(mark(z0))), MARK(s(z0)))
   MARK(from(cons(z0, z1))) -> c7(A__FROM(cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)))
   MARK(from(first(x0, x1))) -> c7(A__FROM(first(mark(x0), mark(x1))), MARK(first(x0, x1)))
   MARK(from(first(x0, first(z0, z1)))) -> c7(A__FROM(a__first(mark(x0), a__first(mark(z0), mark(z1)))), MARK(first(x0, first(z0, z1))))
   MARK(from(first(x0, from(z0)))) -> c7(A__FROM(a__first(mark(x0), a__from(mark(z0)))), MARK(first(x0, from(z0))))
   MARK(from(first(x0, 0))) -> c7(A__FROM(a__first(mark(x0), 0)), MARK(first(x0, 0)))
   MARK(from(first(x0, nil))) -> c7(A__FROM(a__first(mark(x0), nil)), MARK(first(x0, nil)))
   MARK(from(first(x0, s(z0)))) -> c7(A__FROM(a__first(mark(x0), s(mark(z0)))), MARK(first(x0, s(z0))))
   MARK(from(first(x0, cons(z0, z1)))) -> c7(A__FROM(a__first(mark(x0), cons(mark(z0), z1))), MARK(first(x0, cons(z0, z1))))
   MARK(from(first(first(z0, z1), x1))) -> c7(A__FROM(a__first(a__first(mark(z0), mark(z1)), mark(x1))), MARK(first(first(z0, z1), x1)))
   MARK(from(first(from(z0), x1))) -> c7(A__FROM(a__first(a__from(mark(z0)), mark(x1))), MARK(first(from(z0), x1)))
   MARK(from(first(0, x1))) -> c7(A__FROM(a__first(0, mark(x1))), MARK(first(0, x1)))
   MARK(from(first(nil, x1))) -> c7(A__FROM(a__first(nil, mark(x1))), MARK(first(nil, x1)))
   MARK(from(first(s(z0), x1))) -> c7(A__FROM(a__first(s(mark(z0)), mark(x1))), MARK(first(s(z0), x1)))
   MARK(from(first(cons(z0, z1), x1))) -> c7(A__FROM(a__first(cons(mark(z0), z1), mark(x1))), MARK(first(cons(z0, z1), x1)))
   MARK(from(from(x0))) -> c7(A__FROM(cons(mark(mark(x0)), from(s(mark(x0))))), MARK(from(x0)))
   MARK(from(from(x0))) -> c7(A__FROM(from(mark(x0))), MARK(from(x0)))
   MARK(from(from(first(z0, z1)))) -> c7(A__FROM(a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(from(from(from(z0)))) -> c7(A__FROM(a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(from(from(0))) -> c7(A__FROM(a__from(0)), MARK(from(0)))
   MARK(from(from(nil))) -> c7(A__FROM(a__from(nil)), MARK(from(nil)))
   MARK(from(from(s(z0)))) -> c7(A__FROM(a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(from(from(cons(z0, z1)))) -> c7(A__FROM(a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   MARK_1, A__FIRST_2, A__FROM_1

Compound Symbols:   c10_1, c11_1, c5_1, c6_1, c5_2, c6_2, c1_1, c3_1, c7_2


----------------------------------------

(113) CdtRhsSimplificationProcessorProof (BOTH BOUNDS(ID, ID))
Removed 2 trailing tuple parts
----------------------------------------

(114)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
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   A__FIRST(s(z0), cons(first(y0, from(0)), z2)) -> c1(MARK(first(y0, from(0))))
   A__FIRST(s(z0), cons(first(y0, from(nil)), z2)) -> c1(MARK(first(y0, from(nil))))
   A__FIRST(s(z0), cons(first(y0, from(s(y1))), z2)) -> c1(MARK(first(y0, from(s(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(cons(y1, y2))), z2)) -> c1(MARK(first(y0, from(cons(y1, y2)))))
   A__FIRST(s(z0), cons(first(first(y0, y1), from(y2)), z2)) -> c1(MARK(first(first(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(from(y0), from(y1)), z2)) -> c1(MARK(first(from(y0), from(y1))))
   A__FIRST(s(z0), cons(first(s(y0), from(y1)), z2)) -> c1(MARK(first(s(y0), from(y1))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), from(y2)), z2)) -> c1(MARK(first(cons(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(y0, cons(first(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(y0, cons(from(y1), y2)), z2)) -> c1(MARK(first(y0, cons(from(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(0, y1)), z2)) -> c1(MARK(first(y0, cons(0, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(nil, y1)), z2)) -> c1(MARK(first(y0, cons(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(s(y1), y2)), z2)) -> c1(MARK(first(y0, cons(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), cons(y1, y2)), z2)) -> c1(MARK(first(from(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), cons(y1, y2)), z2)) -> c1(MARK(first(s(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(first(y0, first(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(y0, from(y1)), y2), z2)) -> c1(MARK(first(first(y0, from(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, 0), y1), z2)) -> c1(MARK(first(first(y0, 0), y1)))
   A__FIRST(s(z0), cons(first(first(y0, nil), y1), z2)) -> c1(MARK(first(first(y0, nil), y1)))
   A__FIRST(s(z0), cons(first(first(y0, s(y1)), y2), z2)) -> c1(MARK(first(first(y0, s(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, cons(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(first(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(first(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(from(y0), y1), y2), z2)) -> c1(MARK(first(first(from(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(0, y0), y1), z2)) -> c1(MARK(first(first(0, y0), y1)))
   A__FIRST(s(z0), cons(first(first(nil, y0), y1), z2)) -> c1(MARK(first(first(nil, y0), y1)))
   A__FIRST(s(z0), cons(first(first(s(y0), y1), y2), z2)) -> c1(MARK(first(first(s(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(cons(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(y0, y1), 0), z2)) -> c1(MARK(first(first(y0, y1), 0)))
   A__FIRST(s(z0), cons(first(first(y0, y1), nil), z2)) -> c1(MARK(first(first(y0, y1), nil)))
   A__FIRST(s(z0), cons(first(first(y0, y1), s(y2)), z2)) -> c1(MARK(first(first(y0, y1), s(y2))))
   A__FIRST(s(z0), cons(first(first(y0, y1), y2), z2)) -> c1(MARK(first(first(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(from(first(y0, y1)), y2), z2)) -> c1(MARK(first(from(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(from(y0)), y1), z2)) -> c1(MARK(first(from(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(0), y0), z2)) -> c1(MARK(first(from(0), y0)))
   A__FIRST(s(z0), cons(first(from(nil), y0), z2)) -> c1(MARK(first(from(nil), y0)))
   A__FIRST(s(z0), cons(first(from(s(y0)), y1), z2)) -> c1(MARK(first(from(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(cons(y0, y1)), y2), z2)) -> c1(MARK(first(from(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(y0), y1), z2)) -> c1(MARK(first(from(y0), y1)))
   A__FIRST(s(z0), cons(first(from(y0), 0), z2)) -> c1(MARK(first(from(y0), 0)))
   A__FIRST(s(z0), cons(first(from(y0), nil), z2)) -> c1(MARK(first(from(y0), nil)))
   A__FIRST(s(z0), cons(first(from(y0), s(y1)), z2)) -> c1(MARK(first(from(y0), s(y1))))
   A__FIRST(s(z0), cons(first(s(first(y0, y1)), y2), z2)) -> c1(MARK(first(s(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(from(y0)), y1), z2)) -> c1(MARK(first(s(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(0), y0), z2)) -> c1(MARK(first(s(0), y0)))
   A__FIRST(s(z0), cons(first(s(nil), y0), z2)) -> c1(MARK(first(s(nil), y0)))
   A__FIRST(s(z0), cons(first(s(s(y0)), y1), z2)) -> c1(MARK(first(s(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(cons(y0, y1)), y2), z2)) -> c1(MARK(first(s(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(y0), y1), z2)) -> c1(MARK(first(s(y0), y1)))
   A__FIRST(s(z0), cons(first(s(y0), 0), z2)) -> c1(MARK(first(s(y0), 0)))
   A__FIRST(s(z0), cons(first(s(y0), nil), z2)) -> c1(MARK(first(s(y0), nil)))
   A__FIRST(s(z0), cons(first(s(y0), s(y1)), z2)) -> c1(MARK(first(s(y0), s(y1))))
   A__FIRST(s(z0), cons(first(0, first(y0, y1)), z2)) -> c1(MARK(first(0, first(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, first(y0, y1)), z2)) -> c1(MARK(first(nil, first(y0, y1))))
   A__FIRST(s(z0), cons(first(0, from(y0)), z2)) -> c1(MARK(first(0, from(y0))))
   A__FIRST(s(z0), cons(first(nil, from(y0)), z2)) -> c1(MARK(first(nil, from(y0))))
   A__FIRST(s(z0), cons(first(y0, cons(y1, y2)), z2)) -> c1(MARK(first(y0, cons(y1, y2))))
   A__FIRST(s(z0), cons(first(0, cons(y0, y1)), z2)) -> c1(MARK(first(0, cons(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, cons(y0, y1)), z2)) -> c1(MARK(first(nil, cons(y0, y1))))
   MARK(first(x0, cons(0, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c6(MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(MARK(cons(nil, x2)))
   A__FROM(from(y0)) -> c3(MARK(from(y0)))
   A__FROM(s(y0)) -> c3(MARK(s(y0)))
   A__FROM(cons(y0, y1)) -> c3(MARK(cons(y0, y1)))
   A__FROM(first(y0, 0)) -> c3(MARK(first(y0, 0)))
   A__FROM(first(y0, nil)) -> c3(MARK(first(y0, nil)))
   A__FROM(first(y0, s(y1))) -> c3(MARK(first(y0, s(y1))))
   A__FROM(first(cons(y0, y1), y2)) -> c3(MARK(first(cons(y0, y1), y2)))
   A__FROM(first(0, y0)) -> c3(MARK(first(0, y0)))
   A__FROM(first(nil, y0)) -> c3(MARK(first(nil, y0)))
   A__FROM(first(y0, first(y1, first(y2, y3)))) -> c3(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FROM(first(y0, first(y1, from(y2)))) -> c3(MARK(first(y0, first(y1, from(y2)))))
   A__FROM(first(y0, first(y1, 0))) -> c3(MARK(first(y0, first(y1, 0))))
   A__FROM(first(y0, first(y1, nil))) -> c3(MARK(first(y0, first(y1, nil))))
   A__FROM(first(y0, first(y1, s(y2)))) -> c3(MARK(first(y0, first(y1, s(y2)))))
   A__FROM(first(y0, first(y1, cons(y2, y3)))) -> c3(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FROM(first(y0, first(first(y1, y2), y3))) -> c3(MARK(first(y0, first(first(y1, y2), y3))))
   A__FROM(first(y0, first(from(y1), y2))) -> c3(MARK(first(y0, first(from(y1), y2))))
   A__FROM(first(y0, first(0, y1))) -> c3(MARK(first(y0, first(0, y1))))
   A__FROM(first(y0, first(nil, y1))) -> c3(MARK(first(y0, first(nil, y1))))
   A__FROM(first(y0, first(s(y1), y2))) -> c3(MARK(first(y0, first(s(y1), y2))))
   A__FROM(first(y0, first(cons(y1, y2), y3))) -> c3(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), first(y2, y3))) -> c3(MARK(first(first(y0, y1), first(y2, y3))))
   A__FROM(first(from(y0), first(y1, y2))) -> c3(MARK(first(from(y0), first(y1, y2))))
   A__FROM(first(s(y0), first(y1, y2))) -> c3(MARK(first(s(y0), first(y1, y2))))
   A__FROM(first(y0, first(y1, y2))) -> c3(MARK(first(y0, first(y1, y2))))
   A__FROM(first(cons(y0, y1), first(y2, y3))) -> c3(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FROM(first(y0, from(y1))) -> c3(MARK(first(y0, from(y1))))
   A__FROM(first(y0, from(first(y1, y2)))) -> c3(MARK(first(y0, from(first(y1, y2)))))
   A__FROM(first(y0, from(from(y1)))) -> c3(MARK(first(y0, from(from(y1)))))
   A__FROM(first(y0, from(0))) -> c3(MARK(first(y0, from(0))))
   A__FROM(first(y0, from(nil))) -> c3(MARK(first(y0, from(nil))))
   A__FROM(first(y0, from(s(y1)))) -> c3(MARK(first(y0, from(s(y1)))))
   A__FROM(first(y0, from(cons(y1, y2)))) -> c3(MARK(first(y0, from(cons(y1, y2)))))
   A__FROM(first(first(y0, y1), from(y2))) -> c3(MARK(first(first(y0, y1), from(y2))))
   A__FROM(first(from(y0), from(y1))) -> c3(MARK(first(from(y0), from(y1))))
   A__FROM(first(s(y0), from(y1))) -> c3(MARK(first(s(y0), from(y1))))
   A__FROM(first(cons(y0, y1), from(y2))) -> c3(MARK(first(cons(y0, y1), from(y2))))
   A__FROM(first(y0, cons(first(y1, y2), y3))) -> c3(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FROM(first(y0, cons(from(y1), y2))) -> c3(MARK(first(y0, cons(from(y1), y2))))
   A__FROM(first(y0, cons(s(y1), y2))) -> c3(MARK(first(y0, cons(s(y1), y2))))
   A__FROM(first(y0, cons(cons(y1, y2), y3))) -> c3(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), cons(y2, y3))) -> c3(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FROM(first(from(y0), cons(y1, y2))) -> c3(MARK(first(from(y0), cons(y1, y2))))
   A__FROM(first(s(y0), cons(y1, y2))) -> c3(MARK(first(s(y0), cons(y1, y2))))
   A__FROM(first(cons(y0, y1), cons(y2, y3))) -> c3(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FROM(first(first(y0, first(y1, y2)), y3)) -> c3(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FROM(first(first(y0, from(y1)), y2)) -> c3(MARK(first(first(y0, from(y1)), y2)))
   A__FROM(first(first(y0, 0), y1)) -> c3(MARK(first(first(y0, 0), y1)))
   A__FROM(first(first(y0, nil), y1)) -> c3(MARK(first(first(y0, nil), y1)))
   A__FROM(first(first(y0, s(y1)), y2)) -> c3(MARK(first(first(y0, s(y1)), y2)))
   A__FROM(first(first(y0, cons(y1, y2)), y3)) -> c3(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FROM(first(first(first(y0, y1), y2), y3)) -> c3(MARK(first(first(first(y0, y1), y2), y3)))
   A__FROM(first(first(from(y0), y1), y2)) -> c3(MARK(first(first(from(y0), y1), y2)))
   A__FROM(first(first(0, y0), y1)) -> c3(MARK(first(first(0, y0), y1)))
   A__FROM(first(first(nil, y0), y1)) -> c3(MARK(first(first(nil, y0), y1)))
   A__FROM(first(first(s(y0), y1), y2)) -> c3(MARK(first(first(s(y0), y1), y2)))
   A__FROM(first(first(cons(y0, y1), y2), y3)) -> c3(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FROM(first(first(y0, y1), 0)) -> c3(MARK(first(first(y0, y1), 0)))
   A__FROM(first(first(y0, y1), nil)) -> c3(MARK(first(first(y0, y1), nil)))
   A__FROM(first(first(y0, y1), s(y2))) -> c3(MARK(first(first(y0, y1), s(y2))))
   A__FROM(first(first(y0, y1), y2)) -> c3(MARK(first(first(y0, y1), y2)))
   A__FROM(first(from(first(y0, y1)), y2)) -> c3(MARK(first(from(first(y0, y1)), y2)))
   A__FROM(first(from(from(y0)), y1)) -> c3(MARK(first(from(from(y0)), y1)))
   A__FROM(first(from(0), y0)) -> c3(MARK(first(from(0), y0)))
   A__FROM(first(from(nil), y0)) -> c3(MARK(first(from(nil), y0)))
   A__FROM(first(from(s(y0)), y1)) -> c3(MARK(first(from(s(y0)), y1)))
   A__FROM(first(from(cons(y0, y1)), y2)) -> c3(MARK(first(from(cons(y0, y1)), y2)))
   A__FROM(first(from(y0), y1)) -> c3(MARK(first(from(y0), y1)))
   A__FROM(first(from(y0), 0)) -> c3(MARK(first(from(y0), 0)))
   A__FROM(first(from(y0), nil)) -> c3(MARK(first(from(y0), nil)))
   A__FROM(first(from(y0), s(y1))) -> c3(MARK(first(from(y0), s(y1))))
   A__FROM(first(s(first(y0, y1)), y2)) -> c3(MARK(first(s(first(y0, y1)), y2)))
   A__FROM(first(s(from(y0)), y1)) -> c3(MARK(first(s(from(y0)), y1)))
   A__FROM(first(s(0), y0)) -> c3(MARK(first(s(0), y0)))
   A__FROM(first(s(nil), y0)) -> c3(MARK(first(s(nil), y0)))
   A__FROM(first(s(s(y0)), y1)) -> c3(MARK(first(s(s(y0)), y1)))
   A__FROM(first(s(cons(y0, y1)), y2)) -> c3(MARK(first(s(cons(y0, y1)), y2)))
   A__FROM(first(s(y0), y1)) -> c3(MARK(first(s(y0), y1)))
   A__FROM(first(s(y0), 0)) -> c3(MARK(first(s(y0), 0)))
   A__FROM(first(s(y0), nil)) -> c3(MARK(first(s(y0), nil)))
   A__FROM(first(s(y0), s(y1))) -> c3(MARK(first(s(y0), s(y1))))
   A__FROM(first(0, first(y0, y1))) -> c3(MARK(first(0, first(y0, y1))))
   A__FROM(first(nil, first(y0, y1))) -> c3(MARK(first(nil, first(y0, y1))))
   A__FROM(first(0, from(y0))) -> c3(MARK(first(0, from(y0))))
   A__FROM(first(nil, from(y0))) -> c3(MARK(first(nil, from(y0))))
   A__FROM(first(y0, cons(y1, y2))) -> c3(MARK(first(y0, cons(y1, y2))))
   A__FROM(first(0, cons(y0, y1))) -> c3(MARK(first(0, cons(y0, y1))))
   A__FROM(first(nil, cons(y0, y1))) -> c3(MARK(first(nil, cons(y0, y1))))
   A__FROM(first(y0, cons(0, y1))) -> c3(MARK(first(y0, cons(0, y1))))
   A__FROM(first(y0, cons(nil, y1))) -> c3(MARK(first(y0, cons(nil, y1))))
   MARK(from(s(z0))) -> c7(A__FROM(s(mark(z0))), MARK(s(z0)))
   MARK(from(cons(z0, z1))) -> c7(A__FROM(cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)))
   MARK(from(first(x0, x1))) -> c7(A__FROM(first(mark(x0), mark(x1))), MARK(first(x0, x1)))
   MARK(from(first(x0, first(z0, z1)))) -> c7(A__FROM(a__first(mark(x0), a__first(mark(z0), mark(z1)))), MARK(first(x0, first(z0, z1))))
   MARK(from(first(x0, from(z0)))) -> c7(A__FROM(a__first(mark(x0), a__from(mark(z0)))), MARK(first(x0, from(z0))))
   MARK(from(first(x0, 0))) -> c7(A__FROM(a__first(mark(x0), 0)), MARK(first(x0, 0)))
   MARK(from(first(x0, nil))) -> c7(A__FROM(a__first(mark(x0), nil)), MARK(first(x0, nil)))
   MARK(from(first(x0, s(z0)))) -> c7(A__FROM(a__first(mark(x0), s(mark(z0)))), MARK(first(x0, s(z0))))
   MARK(from(first(x0, cons(z0, z1)))) -> c7(A__FROM(a__first(mark(x0), cons(mark(z0), z1))), MARK(first(x0, cons(z0, z1))))
   MARK(from(first(first(z0, z1), x1))) -> c7(A__FROM(a__first(a__first(mark(z0), mark(z1)), mark(x1))), MARK(first(first(z0, z1), x1)))
   MARK(from(first(from(z0), x1))) -> c7(A__FROM(a__first(a__from(mark(z0)), mark(x1))), MARK(first(from(z0), x1)))
   MARK(from(first(0, x1))) -> c7(A__FROM(a__first(0, mark(x1))), MARK(first(0, x1)))
   MARK(from(first(nil, x1))) -> c7(A__FROM(a__first(nil, mark(x1))), MARK(first(nil, x1)))
   MARK(from(first(s(z0), x1))) -> c7(A__FROM(a__first(s(mark(z0)), mark(x1))), MARK(first(s(z0), x1)))
   MARK(from(first(cons(z0, z1), x1))) -> c7(A__FROM(a__first(cons(mark(z0), z1), mark(x1))), MARK(first(cons(z0, z1), x1)))
   MARK(from(from(x0))) -> c7(A__FROM(cons(mark(mark(x0)), from(s(mark(x0))))), MARK(from(x0)))
   MARK(from(from(x0))) -> c7(A__FROM(from(mark(x0))), MARK(from(x0)))
   MARK(from(from(first(z0, z1)))) -> c7(A__FROM(a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(from(from(from(z0)))) -> c7(A__FROM(a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(from(from(s(z0)))) -> c7(A__FROM(a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(from(from(cons(z0, z1)))) -> c7(A__FROM(a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(from(from(0))) -> c7(A__FROM(a__from(0)))
   MARK(from(from(nil))) -> c7(A__FROM(a__from(nil)))
S tuples:
   MARK(s(z0)) -> c10(MARK(z0))
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
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   A__FIRST(s(z0), cons(first(y0, first(y1, y2)), z2)) -> c1(MARK(first(y0, first(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), first(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FIRST(s(z0), cons(first(y0, from(y1)), z2)) -> c1(MARK(first(y0, from(y1))))
   A__FIRST(s(z0), cons(first(y0, from(first(y1, y2))), z2)) -> c1(MARK(first(y0, from(first(y1, y2)))))
   A__FIRST(s(z0), cons(first(y0, from(from(y1))), z2)) -> c1(MARK(first(y0, from(from(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(0)), z2)) -> c1(MARK(first(y0, from(0))))
   A__FIRST(s(z0), cons(first(y0, from(nil)), z2)) -> c1(MARK(first(y0, from(nil))))
   A__FIRST(s(z0), cons(first(y0, from(s(y1))), z2)) -> c1(MARK(first(y0, from(s(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(cons(y1, y2))), z2)) -> c1(MARK(first(y0, from(cons(y1, y2)))))
   A__FIRST(s(z0), cons(first(first(y0, y1), from(y2)), z2)) -> c1(MARK(first(first(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(from(y0), from(y1)), z2)) -> c1(MARK(first(from(y0), from(y1))))
   A__FIRST(s(z0), cons(first(s(y0), from(y1)), z2)) -> c1(MARK(first(s(y0), from(y1))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), from(y2)), z2)) -> c1(MARK(first(cons(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(y0, cons(first(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(y0, cons(from(y1), y2)), z2)) -> c1(MARK(first(y0, cons(from(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(0, y1)), z2)) -> c1(MARK(first(y0, cons(0, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(nil, y1)), z2)) -> c1(MARK(first(y0, cons(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(s(y1), y2)), z2)) -> c1(MARK(first(y0, cons(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), cons(y1, y2)), z2)) -> c1(MARK(first(from(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), cons(y1, y2)), z2)) -> c1(MARK(first(s(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(first(y0, first(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(y0, from(y1)), y2), z2)) -> c1(MARK(first(first(y0, from(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, 0), y1), z2)) -> c1(MARK(first(first(y0, 0), y1)))
   A__FIRST(s(z0), cons(first(first(y0, nil), y1), z2)) -> c1(MARK(first(first(y0, nil), y1)))
   A__FIRST(s(z0), cons(first(first(y0, s(y1)), y2), z2)) -> c1(MARK(first(first(y0, s(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, cons(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(first(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(first(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(from(y0), y1), y2), z2)) -> c1(MARK(first(first(from(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(0, y0), y1), z2)) -> c1(MARK(first(first(0, y0), y1)))
   A__FIRST(s(z0), cons(first(first(nil, y0), y1), z2)) -> c1(MARK(first(first(nil, y0), y1)))
   A__FIRST(s(z0), cons(first(first(s(y0), y1), y2), z2)) -> c1(MARK(first(first(s(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(cons(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(y0, y1), 0), z2)) -> c1(MARK(first(first(y0, y1), 0)))
   A__FIRST(s(z0), cons(first(first(y0, y1), nil), z2)) -> c1(MARK(first(first(y0, y1), nil)))
   A__FIRST(s(z0), cons(first(first(y0, y1), s(y2)), z2)) -> c1(MARK(first(first(y0, y1), s(y2))))
   A__FIRST(s(z0), cons(first(first(y0, y1), y2), z2)) -> c1(MARK(first(first(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(from(first(y0, y1)), y2), z2)) -> c1(MARK(first(from(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(from(y0)), y1), z2)) -> c1(MARK(first(from(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(0), y0), z2)) -> c1(MARK(first(from(0), y0)))
   A__FIRST(s(z0), cons(first(from(nil), y0), z2)) -> c1(MARK(first(from(nil), y0)))
   A__FIRST(s(z0), cons(first(from(s(y0)), y1), z2)) -> c1(MARK(first(from(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(cons(y0, y1)), y2), z2)) -> c1(MARK(first(from(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(y0), y1), z2)) -> c1(MARK(first(from(y0), y1)))
   A__FIRST(s(z0), cons(first(from(y0), 0), z2)) -> c1(MARK(first(from(y0), 0)))
   A__FIRST(s(z0), cons(first(from(y0), nil), z2)) -> c1(MARK(first(from(y0), nil)))
   A__FIRST(s(z0), cons(first(from(y0), s(y1)), z2)) -> c1(MARK(first(from(y0), s(y1))))
   A__FIRST(s(z0), cons(first(s(first(y0, y1)), y2), z2)) -> c1(MARK(first(s(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(from(y0)), y1), z2)) -> c1(MARK(first(s(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(0), y0), z2)) -> c1(MARK(first(s(0), y0)))
   A__FIRST(s(z0), cons(first(s(nil), y0), z2)) -> c1(MARK(first(s(nil), y0)))
   A__FIRST(s(z0), cons(first(s(s(y0)), y1), z2)) -> c1(MARK(first(s(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(cons(y0, y1)), y2), z2)) -> c1(MARK(first(s(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(y0), y1), z2)) -> c1(MARK(first(s(y0), y1)))
   A__FIRST(s(z0), cons(first(s(y0), 0), z2)) -> c1(MARK(first(s(y0), 0)))
   A__FIRST(s(z0), cons(first(s(y0), nil), z2)) -> c1(MARK(first(s(y0), nil)))
   A__FIRST(s(z0), cons(first(s(y0), s(y1)), z2)) -> c1(MARK(first(s(y0), s(y1))))
   A__FIRST(s(z0), cons(first(0, first(y0, y1)), z2)) -> c1(MARK(first(0, first(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, first(y0, y1)), z2)) -> c1(MARK(first(nil, first(y0, y1))))
   A__FIRST(s(z0), cons(first(0, from(y0)), z2)) -> c1(MARK(first(0, from(y0))))
   A__FIRST(s(z0), cons(first(nil, from(y0)), z2)) -> c1(MARK(first(nil, from(y0))))
   A__FIRST(s(z0), cons(first(y0, cons(y1, y2)), z2)) -> c1(MARK(first(y0, cons(y1, y2))))
   A__FIRST(s(z0), cons(first(0, cons(y0, y1)), z2)) -> c1(MARK(first(0, cons(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, cons(y0, y1)), z2)) -> c1(MARK(first(nil, cons(y0, y1))))
   MARK(first(x0, cons(0, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c6(MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(MARK(cons(nil, x2)))
   A__FROM(from(y0)) -> c3(MARK(from(y0)))
   A__FROM(s(y0)) -> c3(MARK(s(y0)))
   A__FROM(cons(y0, y1)) -> c3(MARK(cons(y0, y1)))
   A__FROM(first(y0, 0)) -> c3(MARK(first(y0, 0)))
   A__FROM(first(y0, nil)) -> c3(MARK(first(y0, nil)))
   A__FROM(first(y0, s(y1))) -> c3(MARK(first(y0, s(y1))))
   A__FROM(first(cons(y0, y1), y2)) -> c3(MARK(first(cons(y0, y1), y2)))
   A__FROM(first(0, y0)) -> c3(MARK(first(0, y0)))
   A__FROM(first(nil, y0)) -> c3(MARK(first(nil, y0)))
   A__FROM(first(y0, first(y1, first(y2, y3)))) -> c3(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FROM(first(y0, first(y1, from(y2)))) -> c3(MARK(first(y0, first(y1, from(y2)))))
   A__FROM(first(y0, first(y1, 0))) -> c3(MARK(first(y0, first(y1, 0))))
   A__FROM(first(y0, first(y1, nil))) -> c3(MARK(first(y0, first(y1, nil))))
   A__FROM(first(y0, first(y1, s(y2)))) -> c3(MARK(first(y0, first(y1, s(y2)))))
   A__FROM(first(y0, first(y1, cons(y2, y3)))) -> c3(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FROM(first(y0, first(first(y1, y2), y3))) -> c3(MARK(first(y0, first(first(y1, y2), y3))))
   A__FROM(first(y0, first(from(y1), y2))) -> c3(MARK(first(y0, first(from(y1), y2))))
   A__FROM(first(y0, first(0, y1))) -> c3(MARK(first(y0, first(0, y1))))
   A__FROM(first(y0, first(nil, y1))) -> c3(MARK(first(y0, first(nil, y1))))
   A__FROM(first(y0, first(s(y1), y2))) -> c3(MARK(first(y0, first(s(y1), y2))))
   A__FROM(first(y0, first(cons(y1, y2), y3))) -> c3(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), first(y2, y3))) -> c3(MARK(first(first(y0, y1), first(y2, y3))))
   A__FROM(first(from(y0), first(y1, y2))) -> c3(MARK(first(from(y0), first(y1, y2))))
   A__FROM(first(s(y0), first(y1, y2))) -> c3(MARK(first(s(y0), first(y1, y2))))
   A__FROM(first(y0, first(y1, y2))) -> c3(MARK(first(y0, first(y1, y2))))
   A__FROM(first(cons(y0, y1), first(y2, y3))) -> c3(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FROM(first(y0, from(y1))) -> c3(MARK(first(y0, from(y1))))
   A__FROM(first(y0, from(first(y1, y2)))) -> c3(MARK(first(y0, from(first(y1, y2)))))
   A__FROM(first(y0, from(from(y1)))) -> c3(MARK(first(y0, from(from(y1)))))
   A__FROM(first(y0, from(0))) -> c3(MARK(first(y0, from(0))))
   A__FROM(first(y0, from(nil))) -> c3(MARK(first(y0, from(nil))))
   A__FROM(first(y0, from(s(y1)))) -> c3(MARK(first(y0, from(s(y1)))))
   A__FROM(first(y0, from(cons(y1, y2)))) -> c3(MARK(first(y0, from(cons(y1, y2)))))
   A__FROM(first(first(y0, y1), from(y2))) -> c3(MARK(first(first(y0, y1), from(y2))))
   A__FROM(first(from(y0), from(y1))) -> c3(MARK(first(from(y0), from(y1))))
   A__FROM(first(s(y0), from(y1))) -> c3(MARK(first(s(y0), from(y1))))
   A__FROM(first(cons(y0, y1), from(y2))) -> c3(MARK(first(cons(y0, y1), from(y2))))
   A__FROM(first(y0, cons(first(y1, y2), y3))) -> c3(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FROM(first(y0, cons(from(y1), y2))) -> c3(MARK(first(y0, cons(from(y1), y2))))
   A__FROM(first(y0, cons(s(y1), y2))) -> c3(MARK(first(y0, cons(s(y1), y2))))
   A__FROM(first(y0, cons(cons(y1, y2), y3))) -> c3(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), cons(y2, y3))) -> c3(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FROM(first(from(y0), cons(y1, y2))) -> c3(MARK(first(from(y0), cons(y1, y2))))
   A__FROM(first(s(y0), cons(y1, y2))) -> c3(MARK(first(s(y0), cons(y1, y2))))
   A__FROM(first(cons(y0, y1), cons(y2, y3))) -> c3(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FROM(first(first(y0, first(y1, y2)), y3)) -> c3(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FROM(first(first(y0, from(y1)), y2)) -> c3(MARK(first(first(y0, from(y1)), y2)))
   A__FROM(first(first(y0, 0), y1)) -> c3(MARK(first(first(y0, 0), y1)))
   A__FROM(first(first(y0, nil), y1)) -> c3(MARK(first(first(y0, nil), y1)))
   A__FROM(first(first(y0, s(y1)), y2)) -> c3(MARK(first(first(y0, s(y1)), y2)))
   A__FROM(first(first(y0, cons(y1, y2)), y3)) -> c3(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FROM(first(first(first(y0, y1), y2), y3)) -> c3(MARK(first(first(first(y0, y1), y2), y3)))
   A__FROM(first(first(from(y0), y1), y2)) -> c3(MARK(first(first(from(y0), y1), y2)))
   A__FROM(first(first(0, y0), y1)) -> c3(MARK(first(first(0, y0), y1)))
   A__FROM(first(first(nil, y0), y1)) -> c3(MARK(first(first(nil, y0), y1)))
   A__FROM(first(first(s(y0), y1), y2)) -> c3(MARK(first(first(s(y0), y1), y2)))
   A__FROM(first(first(cons(y0, y1), y2), y3)) -> c3(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FROM(first(first(y0, y1), 0)) -> c3(MARK(first(first(y0, y1), 0)))
   A__FROM(first(first(y0, y1), nil)) -> c3(MARK(first(first(y0, y1), nil)))
   A__FROM(first(first(y0, y1), s(y2))) -> c3(MARK(first(first(y0, y1), s(y2))))
   A__FROM(first(first(y0, y1), y2)) -> c3(MARK(first(first(y0, y1), y2)))
   A__FROM(first(from(first(y0, y1)), y2)) -> c3(MARK(first(from(first(y0, y1)), y2)))
   A__FROM(first(from(from(y0)), y1)) -> c3(MARK(first(from(from(y0)), y1)))
   A__FROM(first(from(0), y0)) -> c3(MARK(first(from(0), y0)))
   A__FROM(first(from(nil), y0)) -> c3(MARK(first(from(nil), y0)))
   A__FROM(first(from(s(y0)), y1)) -> c3(MARK(first(from(s(y0)), y1)))
   A__FROM(first(from(cons(y0, y1)), y2)) -> c3(MARK(first(from(cons(y0, y1)), y2)))
   A__FROM(first(from(y0), y1)) -> c3(MARK(first(from(y0), y1)))
   A__FROM(first(from(y0), 0)) -> c3(MARK(first(from(y0), 0)))
   A__FROM(first(from(y0), nil)) -> c3(MARK(first(from(y0), nil)))
   A__FROM(first(from(y0), s(y1))) -> c3(MARK(first(from(y0), s(y1))))
   A__FROM(first(s(first(y0, y1)), y2)) -> c3(MARK(first(s(first(y0, y1)), y2)))
   A__FROM(first(s(from(y0)), y1)) -> c3(MARK(first(s(from(y0)), y1)))
   A__FROM(first(s(0), y0)) -> c3(MARK(first(s(0), y0)))
   A__FROM(first(s(nil), y0)) -> c3(MARK(first(s(nil), y0)))
   A__FROM(first(s(s(y0)), y1)) -> c3(MARK(first(s(s(y0)), y1)))
   A__FROM(first(s(cons(y0, y1)), y2)) -> c3(MARK(first(s(cons(y0, y1)), y2)))
   A__FROM(first(s(y0), y1)) -> c3(MARK(first(s(y0), y1)))
   A__FROM(first(s(y0), 0)) -> c3(MARK(first(s(y0), 0)))
   A__FROM(first(s(y0), nil)) -> c3(MARK(first(s(y0), nil)))
   A__FROM(first(s(y0), s(y1))) -> c3(MARK(first(s(y0), s(y1))))
   A__FROM(first(0, first(y0, y1))) -> c3(MARK(first(0, first(y0, y1))))
   A__FROM(first(nil, first(y0, y1))) -> c3(MARK(first(nil, first(y0, y1))))
   A__FROM(first(0, from(y0))) -> c3(MARK(first(0, from(y0))))
   A__FROM(first(nil, from(y0))) -> c3(MARK(first(nil, from(y0))))
   A__FROM(first(y0, cons(y1, y2))) -> c3(MARK(first(y0, cons(y1, y2))))
   A__FROM(first(0, cons(y0, y1))) -> c3(MARK(first(0, cons(y0, y1))))
   A__FROM(first(nil, cons(y0, y1))) -> c3(MARK(first(nil, cons(y0, y1))))
   A__FROM(first(y0, cons(0, y1))) -> c3(MARK(first(y0, cons(0, y1))))
   A__FROM(first(y0, cons(nil, y1))) -> c3(MARK(first(y0, cons(nil, y1))))
   MARK(from(s(z0))) -> c7(A__FROM(s(mark(z0))), MARK(s(z0)))
   MARK(from(cons(z0, z1))) -> c7(A__FROM(cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)))
   MARK(from(first(x0, x1))) -> c7(A__FROM(first(mark(x0), mark(x1))), MARK(first(x0, x1)))
   MARK(from(first(x0, first(z0, z1)))) -> c7(A__FROM(a__first(mark(x0), a__first(mark(z0), mark(z1)))), MARK(first(x0, first(z0, z1))))
   MARK(from(first(x0, from(z0)))) -> c7(A__FROM(a__first(mark(x0), a__from(mark(z0)))), MARK(first(x0, from(z0))))
   MARK(from(first(x0, 0))) -> c7(A__FROM(a__first(mark(x0), 0)), MARK(first(x0, 0)))
   MARK(from(first(x0, nil))) -> c7(A__FROM(a__first(mark(x0), nil)), MARK(first(x0, nil)))
   MARK(from(first(x0, s(z0)))) -> c7(A__FROM(a__first(mark(x0), s(mark(z0)))), MARK(first(x0, s(z0))))
   MARK(from(first(x0, cons(z0, z1)))) -> c7(A__FROM(a__first(mark(x0), cons(mark(z0), z1))), MARK(first(x0, cons(z0, z1))))
   MARK(from(first(first(z0, z1), x1))) -> c7(A__FROM(a__first(a__first(mark(z0), mark(z1)), mark(x1))), MARK(first(first(z0, z1), x1)))
   MARK(from(first(from(z0), x1))) -> c7(A__FROM(a__first(a__from(mark(z0)), mark(x1))), MARK(first(from(z0), x1)))
   MARK(from(first(0, x1))) -> c7(A__FROM(a__first(0, mark(x1))), MARK(first(0, x1)))
   MARK(from(first(nil, x1))) -> c7(A__FROM(a__first(nil, mark(x1))), MARK(first(nil, x1)))
   MARK(from(first(s(z0), x1))) -> c7(A__FROM(a__first(s(mark(z0)), mark(x1))), MARK(first(s(z0), x1)))
   MARK(from(first(cons(z0, z1), x1))) -> c7(A__FROM(a__first(cons(mark(z0), z1), mark(x1))), MARK(first(cons(z0, z1), x1)))
   MARK(from(from(x0))) -> c7(A__FROM(cons(mark(mark(x0)), from(s(mark(x0))))), MARK(from(x0)))
   MARK(from(from(x0))) -> c7(A__FROM(from(mark(x0))), MARK(from(x0)))
   MARK(from(from(first(z0, z1)))) -> c7(A__FROM(a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(from(from(from(z0)))) -> c7(A__FROM(a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(from(from(s(z0)))) -> c7(A__FROM(a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(from(from(cons(z0, z1)))) -> c7(A__FROM(a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(from(from(0))) -> c7(A__FROM(a__from(0)))
   MARK(from(from(nil))) -> c7(A__FROM(a__from(nil)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   MARK_1, A__FIRST_2, A__FROM_1

Compound Symbols:   c10_1, c11_1, c5_1, c6_1, c5_2, c6_2, c1_1, c3_1, c7_2, c7_1


----------------------------------------

(115) CdtForwardInstantiationProof (BOTH BOUNDS(ID, ID))
Use forward instantiation to replace MARK(s(z0)) -> c10(MARK(z0)) by 
   MARK(s(s(y0))) -> c10(MARK(s(y0)))
   MARK(s(cons(y0, y1))) -> c10(MARK(cons(y0, y1)))
   MARK(s(first(y0, 0))) -> c10(MARK(first(y0, 0)))
   MARK(s(first(y0, nil))) -> c10(MARK(first(y0, nil)))
   MARK(s(first(y0, s(y1)))) -> c10(MARK(first(y0, s(y1))))
   MARK(s(first(cons(y0, y1), y2))) -> c10(MARK(first(cons(y0, y1), y2)))
   MARK(s(first(0, y0))) -> c10(MARK(first(0, y0)))
   MARK(s(first(nil, y0))) -> c10(MARK(first(nil, y0)))
   MARK(s(first(y0, first(y1, first(y2, y3))))) -> c10(MARK(first(y0, first(y1, first(y2, y3)))))
   MARK(s(first(y0, first(y1, from(y2))))) -> c10(MARK(first(y0, first(y1, from(y2)))))
   MARK(s(first(y0, first(y1, 0)))) -> c10(MARK(first(y0, first(y1, 0))))
   MARK(s(first(y0, first(y1, nil)))) -> c10(MARK(first(y0, first(y1, nil))))
   MARK(s(first(y0, first(y1, s(y2))))) -> c10(MARK(first(y0, first(y1, s(y2)))))
   MARK(s(first(y0, first(y1, cons(y2, y3))))) -> c10(MARK(first(y0, first(y1, cons(y2, y3)))))
   MARK(s(first(y0, first(first(y1, y2), y3)))) -> c10(MARK(first(y0, first(first(y1, y2), y3))))
   MARK(s(first(y0, first(from(y1), y2)))) -> c10(MARK(first(y0, first(from(y1), y2))))
   MARK(s(first(y0, first(0, y1)))) -> c10(MARK(first(y0, first(0, y1))))
   MARK(s(first(y0, first(nil, y1)))) -> c10(MARK(first(y0, first(nil, y1))))
   MARK(s(first(y0, first(s(y1), y2)))) -> c10(MARK(first(y0, first(s(y1), y2))))
   MARK(s(first(y0, first(cons(y1, y2), y3)))) -> c10(MARK(first(y0, first(cons(y1, y2), y3))))
   MARK(s(first(first(y0, y1), first(y2, y3)))) -> c10(MARK(first(first(y0, y1), first(y2, y3))))
   MARK(s(first(from(y0), first(y1, y2)))) -> c10(MARK(first(from(y0), first(y1, y2))))
   MARK(s(first(s(y0), first(y1, y2)))) -> c10(MARK(first(s(y0), first(y1, y2))))
   MARK(s(first(y0, first(y1, y2)))) -> c10(MARK(first(y0, first(y1, y2))))
   MARK(s(first(cons(y0, y1), first(y2, y3)))) -> c10(MARK(first(cons(y0, y1), first(y2, y3))))
   MARK(s(first(y0, from(y1)))) -> c10(MARK(first(y0, from(y1))))
   MARK(s(first(y0, from(first(y1, y2))))) -> c10(MARK(first(y0, from(first(y1, y2)))))
   MARK(s(first(y0, from(from(y1))))) -> c10(MARK(first(y0, from(from(y1)))))
   MARK(s(first(y0, from(0)))) -> c10(MARK(first(y0, from(0))))
   MARK(s(first(y0, from(nil)))) -> c10(MARK(first(y0, from(nil))))
   MARK(s(first(y0, from(s(y1))))) -> c10(MARK(first(y0, from(s(y1)))))
   MARK(s(first(y0, from(cons(y1, y2))))) -> c10(MARK(first(y0, from(cons(y1, y2)))))
   MARK(s(first(first(y0, y1), from(y2)))) -> c10(MARK(first(first(y0, y1), from(y2))))
   MARK(s(first(from(y0), from(y1)))) -> c10(MARK(first(from(y0), from(y1))))
   MARK(s(first(s(y0), from(y1)))) -> c10(MARK(first(s(y0), from(y1))))
   MARK(s(first(cons(y0, y1), from(y2)))) -> c10(MARK(first(cons(y0, y1), from(y2))))
   MARK(s(first(y0, cons(first(y1, y2), y3)))) -> c10(MARK(first(y0, cons(first(y1, y2), y3))))
   MARK(s(first(y0, cons(from(y1), y2)))) -> c10(MARK(first(y0, cons(from(y1), y2))))
   MARK(s(first(y0, cons(s(y1), y2)))) -> c10(MARK(first(y0, cons(s(y1), y2))))
   MARK(s(first(y0, cons(cons(y1, y2), y3)))) -> c10(MARK(first(y0, cons(cons(y1, y2), y3))))
   MARK(s(first(first(y0, y1), cons(y2, y3)))) -> c10(MARK(first(first(y0, y1), cons(y2, y3))))
   MARK(s(first(from(y0), cons(y1, y2)))) -> c10(MARK(first(from(y0), cons(y1, y2))))
   MARK(s(first(s(y0), cons(y1, y2)))) -> c10(MARK(first(s(y0), cons(y1, y2))))
   MARK(s(first(cons(y0, y1), cons(y2, y3)))) -> c10(MARK(first(cons(y0, y1), cons(y2, y3))))
   MARK(s(first(first(y0, first(y1, y2)), y3))) -> c10(MARK(first(first(y0, first(y1, y2)), y3)))
   MARK(s(first(first(y0, from(y1)), y2))) -> c10(MARK(first(first(y0, from(y1)), y2)))
   MARK(s(first(first(y0, 0), y1))) -> c10(MARK(first(first(y0, 0), y1)))
   MARK(s(first(first(y0, nil), y1))) -> c10(MARK(first(first(y0, nil), y1)))
   MARK(s(first(first(y0, s(y1)), y2))) -> c10(MARK(first(first(y0, s(y1)), y2)))
   MARK(s(first(first(y0, cons(y1, y2)), y3))) -> c10(MARK(first(first(y0, cons(y1, y2)), y3)))
   MARK(s(first(first(first(y0, y1), y2), y3))) -> c10(MARK(first(first(first(y0, y1), y2), y3)))
   MARK(s(first(first(from(y0), y1), y2))) -> c10(MARK(first(first(from(y0), y1), y2)))
   MARK(s(first(first(0, y0), y1))) -> c10(MARK(first(first(0, y0), y1)))
   MARK(s(first(first(nil, y0), y1))) -> c10(MARK(first(first(nil, y0), y1)))
   MARK(s(first(first(s(y0), y1), y2))) -> c10(MARK(first(first(s(y0), y1), y2)))
   MARK(s(first(first(cons(y0, y1), y2), y3))) -> c10(MARK(first(first(cons(y0, y1), y2), y3)))
   MARK(s(first(first(y0, y1), 0))) -> c10(MARK(first(first(y0, y1), 0)))
   MARK(s(first(first(y0, y1), nil))) -> c10(MARK(first(first(y0, y1), nil)))
   MARK(s(first(first(y0, y1), s(y2)))) -> c10(MARK(first(first(y0, y1), s(y2))))
   MARK(s(first(first(y0, y1), y2))) -> c10(MARK(first(first(y0, y1), y2)))
   MARK(s(first(from(first(y0, y1)), y2))) -> c10(MARK(first(from(first(y0, y1)), y2)))
   MARK(s(first(from(from(y0)), y1))) -> c10(MARK(first(from(from(y0)), y1)))
   MARK(s(first(from(s(y0)), y1))) -> c10(MARK(first(from(s(y0)), y1)))
   MARK(s(first(from(cons(y0, y1)), y2))) -> c10(MARK(first(from(cons(y0, y1)), y2)))
   MARK(s(first(from(y0), y1))) -> c10(MARK(first(from(y0), y1)))
   MARK(s(first(from(y0), 0))) -> c10(MARK(first(from(y0), 0)))
   MARK(s(first(from(y0), nil))) -> c10(MARK(first(from(y0), nil)))
   MARK(s(first(from(y0), s(y1)))) -> c10(MARK(first(from(y0), s(y1))))
   MARK(s(first(s(first(y0, y1)), y2))) -> c10(MARK(first(s(first(y0, y1)), y2)))
   MARK(s(first(s(from(y0)), y1))) -> c10(MARK(first(s(from(y0)), y1)))
   MARK(s(first(s(0), y0))) -> c10(MARK(first(s(0), y0)))
   MARK(s(first(s(nil), y0))) -> c10(MARK(first(s(nil), y0)))
   MARK(s(first(s(s(y0)), y1))) -> c10(MARK(first(s(s(y0)), y1)))
   MARK(s(first(s(cons(y0, y1)), y2))) -> c10(MARK(first(s(cons(y0, y1)), y2)))
   MARK(s(first(s(y0), y1))) -> c10(MARK(first(s(y0), y1)))
   MARK(s(first(s(y0), 0))) -> c10(MARK(first(s(y0), 0)))
   MARK(s(first(s(y0), nil))) -> c10(MARK(first(s(y0), nil)))
   MARK(s(first(s(y0), s(y1)))) -> c10(MARK(first(s(y0), s(y1))))
   MARK(s(first(0, first(y0, y1)))) -> c10(MARK(first(0, first(y0, y1))))
   MARK(s(first(nil, first(y0, y1)))) -> c10(MARK(first(nil, first(y0, y1))))
   MARK(s(first(0, from(y0)))) -> c10(MARK(first(0, from(y0))))
   MARK(s(first(nil, from(y0)))) -> c10(MARK(first(nil, from(y0))))
   MARK(s(first(y0, cons(y1, y2)))) -> c10(MARK(first(y0, cons(y1, y2))))
   MARK(s(first(0, cons(y0, y1)))) -> c10(MARK(first(0, cons(y0, y1))))
   MARK(s(first(nil, cons(y0, y1)))) -> c10(MARK(first(nil, cons(y0, y1))))
   MARK(s(first(from(0), y0))) -> c10(MARK(first(from(0), y0)))
   MARK(s(first(from(nil), y0))) -> c10(MARK(first(from(nil), y0)))
   MARK(s(first(y0, cons(0, y1)))) -> c10(MARK(first(y0, cons(0, y1))))
   MARK(s(first(y0, cons(nil, y1)))) -> c10(MARK(first(y0, cons(nil, y1))))
   MARK(s(from(s(y0)))) -> c10(MARK(from(s(y0))))
   MARK(s(from(cons(y0, y1)))) -> c10(MARK(from(cons(y0, y1))))
   MARK(s(from(first(y0, y1)))) -> c10(MARK(from(first(y0, y1))))
   MARK(s(from(first(y0, first(y1, y2))))) -> c10(MARK(from(first(y0, first(y1, y2)))))
   MARK(s(from(first(y0, from(y1))))) -> c10(MARK(from(first(y0, from(y1)))))
   MARK(s(from(first(y0, 0)))) -> c10(MARK(from(first(y0, 0))))
   MARK(s(from(first(y0, nil)))) -> c10(MARK(from(first(y0, nil))))
   MARK(s(from(first(y0, s(y1))))) -> c10(MARK(from(first(y0, s(y1)))))
   MARK(s(from(first(y0, cons(y1, y2))))) -> c10(MARK(from(first(y0, cons(y1, y2)))))
   MARK(s(from(first(first(y0, y1), y2)))) -> c10(MARK(from(first(first(y0, y1), y2))))
   MARK(s(from(first(from(y0), y1)))) -> c10(MARK(from(first(from(y0), y1))))
   MARK(s(from(first(0, y0)))) -> c10(MARK(from(first(0, y0))))
   MARK(s(from(first(nil, y0)))) -> c10(MARK(from(first(nil, y0))))
   MARK(s(from(first(s(y0), y1)))) -> c10(MARK(from(first(s(y0), y1))))
   MARK(s(from(first(cons(y0, y1), y2)))) -> c10(MARK(from(first(cons(y0, y1), y2))))
   MARK(s(from(from(y0)))) -> c10(MARK(from(from(y0))))
   MARK(s(from(from(first(y0, y1))))) -> c10(MARK(from(from(first(y0, y1)))))
   MARK(s(from(from(from(y0))))) -> c10(MARK(from(from(from(y0)))))
   MARK(s(from(from(s(y0))))) -> c10(MARK(from(from(s(y0)))))
   MARK(s(from(from(cons(y0, y1))))) -> c10(MARK(from(from(cons(y0, y1)))))
   MARK(s(from(from(0)))) -> c10(MARK(from(from(0))))
   MARK(s(from(from(nil)))) -> c10(MARK(from(from(nil))))

----------------------------------------

(116)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
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   MARK(s(first(nil, from(y0)))) -> c10(MARK(first(nil, from(y0))))
   MARK(s(first(y0, cons(y1, y2)))) -> c10(MARK(first(y0, cons(y1, y2))))
   MARK(s(first(0, cons(y0, y1)))) -> c10(MARK(first(0, cons(y0, y1))))
   MARK(s(first(nil, cons(y0, y1)))) -> c10(MARK(first(nil, cons(y0, y1))))
   MARK(s(first(from(0), y0))) -> c10(MARK(first(from(0), y0)))
   MARK(s(first(from(nil), y0))) -> c10(MARK(first(from(nil), y0)))
   MARK(s(first(y0, cons(0, y1)))) -> c10(MARK(first(y0, cons(0, y1))))
   MARK(s(first(y0, cons(nil, y1)))) -> c10(MARK(first(y0, cons(nil, y1))))
   MARK(s(from(s(y0)))) -> c10(MARK(from(s(y0))))
   MARK(s(from(cons(y0, y1)))) -> c10(MARK(from(cons(y0, y1))))
   MARK(s(from(first(y0, y1)))) -> c10(MARK(from(first(y0, y1))))
   MARK(s(from(first(y0, first(y1, y2))))) -> c10(MARK(from(first(y0, first(y1, y2)))))
   MARK(s(from(first(y0, from(y1))))) -> c10(MARK(from(first(y0, from(y1)))))
   MARK(s(from(first(y0, 0)))) -> c10(MARK(from(first(y0, 0))))
   MARK(s(from(first(y0, nil)))) -> c10(MARK(from(first(y0, nil))))
   MARK(s(from(first(y0, s(y1))))) -> c10(MARK(from(first(y0, s(y1)))))
   MARK(s(from(first(y0, cons(y1, y2))))) -> c10(MARK(from(first(y0, cons(y1, y2)))))
   MARK(s(from(first(first(y0, y1), y2)))) -> c10(MARK(from(first(first(y0, y1), y2))))
   MARK(s(from(first(from(y0), y1)))) -> c10(MARK(from(first(from(y0), y1))))
   MARK(s(from(first(0, y0)))) -> c10(MARK(from(first(0, y0))))
   MARK(s(from(first(nil, y0)))) -> c10(MARK(from(first(nil, y0))))
   MARK(s(from(first(s(y0), y1)))) -> c10(MARK(from(first(s(y0), y1))))
   MARK(s(from(first(cons(y0, y1), y2)))) -> c10(MARK(from(first(cons(y0, y1), y2))))
   MARK(s(from(from(y0)))) -> c10(MARK(from(from(y0))))
   MARK(s(from(from(first(y0, y1))))) -> c10(MARK(from(from(first(y0, y1)))))
   MARK(s(from(from(from(y0))))) -> c10(MARK(from(from(from(y0)))))
   MARK(s(from(from(s(y0))))) -> c10(MARK(from(from(s(y0)))))
   MARK(s(from(from(cons(y0, y1))))) -> c10(MARK(from(from(cons(y0, y1)))))
   MARK(s(from(from(0)))) -> c10(MARK(from(from(0))))
   MARK(s(from(from(nil)))) -> c10(MARK(from(from(nil))))
S tuples:
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)), MARK(s(0)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)), MARK(s(nil)))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, x1), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(first(x0, x1), x2)) -> c6(MARK(x2))
   MARK(first(from(first(z0, z1)), x1)) -> c6(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(from(from(z0)), x1)) -> c6(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(0), x1)) -> c6(A__FIRST(a__from(0), mark(x1)), MARK(x1))
   MARK(first(from(nil), x1)) -> c6(A__FIRST(a__from(nil), mark(x1)), MARK(x1))
   MARK(first(from(s(z0)), x1)) -> c6(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(cons(z0, z1)), x1)) -> c6(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(x1))
   MARK(first(from(x0), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(from(x0), x1)) -> c6(MARK(x1))
   MARK(first(s(first(z0, z1)), x1)) -> c6(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(s(from(z0)), x1)) -> c6(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(0), x1)) -> c6(A__FIRST(s(0), mark(x1)), MARK(x1))
   MARK(first(s(nil), x1)) -> c6(A__FIRST(s(nil), mark(x1)), MARK(x1))
   MARK(first(s(s(z0)), x1)) -> c6(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(cons(z0, z1)), x1)) -> c6(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(x1))
   MARK(first(s(x0), s(z0))) -> c6(MARK(s(z0)))
   A__FIRST(s(z0), cons(from(y0), z2)) -> c1(MARK(from(y0)))
   A__FIRST(s(z0), cons(s(y0), z2)) -> c1(MARK(s(y0)))
   A__FIRST(s(z0), cons(cons(y0, y1), z2)) -> c1(MARK(cons(y0, y1)))
   A__FIRST(s(z0), cons(first(y0, 0), z2)) -> c1(MARK(first(y0, 0)))
   A__FIRST(s(z0), cons(first(y0, nil), z2)) -> c1(MARK(first(y0, nil)))
   A__FIRST(s(z0), cons(first(y0, s(y1)), z2)) -> c1(MARK(first(y0, s(y1))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), y2), z2)) -> c1(MARK(first(cons(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(0, y0), z2)) -> c1(MARK(first(0, y0)))
   A__FIRST(s(z0), cons(first(nil, y0), z2)) -> c1(MARK(first(nil, y0)))
   A__FIRST(s(z0), cons(first(y0, first(y1, first(y2, y3))), z2)) -> c1(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FIRST(s(z0), cons(first(y0, first(y1, from(y2))), z2)) -> c1(MARK(first(y0, first(y1, from(y2)))))
   A__FIRST(s(z0), cons(first(y0, first(y1, 0)), z2)) -> c1(MARK(first(y0, first(y1, 0))))
   A__FIRST(s(z0), cons(first(y0, first(y1, nil)), z2)) -> c1(MARK(first(y0, first(y1, nil))))
   A__FIRST(s(z0), cons(first(y0, first(y1, s(y2))), z2)) -> c1(MARK(first(y0, first(y1, s(y2)))))
   A__FIRST(s(z0), cons(first(y0, first(y1, cons(y2, y3))), z2)) -> c1(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FIRST(s(z0), cons(first(y0, first(first(y1, y2), y3)), z2)) -> c1(MARK(first(y0, first(first(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(y0, first(from(y1), y2)), z2)) -> c1(MARK(first(y0, first(from(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, first(0, y1)), z2)) -> c1(MARK(first(y0, first(0, y1))))
   A__FIRST(s(z0), cons(first(y0, first(nil, y1)), z2)) -> c1(MARK(first(y0, first(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, first(s(y1), y2)), z2)) -> c1(MARK(first(y0, first(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, first(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), first(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), first(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), first(y1, y2)), z2)) -> c1(MARK(first(from(y0), first(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), first(y1, y2)), z2)) -> c1(MARK(first(s(y0), first(y1, y2))))
   A__FIRST(s(z0), cons(first(y0, first(y1, y2)), z2)) -> c1(MARK(first(y0, first(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), first(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FIRST(s(z0), cons(first(y0, from(y1)), z2)) -> c1(MARK(first(y0, from(y1))))
   A__FIRST(s(z0), cons(first(y0, from(first(y1, y2))), z2)) -> c1(MARK(first(y0, from(first(y1, y2)))))
   A__FIRST(s(z0), cons(first(y0, from(from(y1))), z2)) -> c1(MARK(first(y0, from(from(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(0)), z2)) -> c1(MARK(first(y0, from(0))))
   A__FIRST(s(z0), cons(first(y0, from(nil)), z2)) -> c1(MARK(first(y0, from(nil))))
   A__FIRST(s(z0), cons(first(y0, from(s(y1))), z2)) -> c1(MARK(first(y0, from(s(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(cons(y1, y2))), z2)) -> c1(MARK(first(y0, from(cons(y1, y2)))))
   A__FIRST(s(z0), cons(first(first(y0, y1), from(y2)), z2)) -> c1(MARK(first(first(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(from(y0), from(y1)), z2)) -> c1(MARK(first(from(y0), from(y1))))
   A__FIRST(s(z0), cons(first(s(y0), from(y1)), z2)) -> c1(MARK(first(s(y0), from(y1))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), from(y2)), z2)) -> c1(MARK(first(cons(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(y0, cons(first(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(y0, cons(from(y1), y2)), z2)) -> c1(MARK(first(y0, cons(from(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(0, y1)), z2)) -> c1(MARK(first(y0, cons(0, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(nil, y1)), z2)) -> c1(MARK(first(y0, cons(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(s(y1), y2)), z2)) -> c1(MARK(first(y0, cons(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), cons(y1, y2)), z2)) -> c1(MARK(first(from(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), cons(y1, y2)), z2)) -> c1(MARK(first(s(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(first(y0, first(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(y0, from(y1)), y2), z2)) -> c1(MARK(first(first(y0, from(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, 0), y1), z2)) -> c1(MARK(first(first(y0, 0), y1)))
   A__FIRST(s(z0), cons(first(first(y0, nil), y1), z2)) -> c1(MARK(first(first(y0, nil), y1)))
   A__FIRST(s(z0), cons(first(first(y0, s(y1)), y2), z2)) -> c1(MARK(first(first(y0, s(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, cons(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(first(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(first(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(from(y0), y1), y2), z2)) -> c1(MARK(first(first(from(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(0, y0), y1), z2)) -> c1(MARK(first(first(0, y0), y1)))
   A__FIRST(s(z0), cons(first(first(nil, y0), y1), z2)) -> c1(MARK(first(first(nil, y0), y1)))
   A__FIRST(s(z0), cons(first(first(s(y0), y1), y2), z2)) -> c1(MARK(first(first(s(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(cons(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(y0, y1), 0), z2)) -> c1(MARK(first(first(y0, y1), 0)))
   A__FIRST(s(z0), cons(first(first(y0, y1), nil), z2)) -> c1(MARK(first(first(y0, y1), nil)))
   A__FIRST(s(z0), cons(first(first(y0, y1), s(y2)), z2)) -> c1(MARK(first(first(y0, y1), s(y2))))
   A__FIRST(s(z0), cons(first(first(y0, y1), y2), z2)) -> c1(MARK(first(first(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(from(first(y0, y1)), y2), z2)) -> c1(MARK(first(from(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(from(y0)), y1), z2)) -> c1(MARK(first(from(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(0), y0), z2)) -> c1(MARK(first(from(0), y0)))
   A__FIRST(s(z0), cons(first(from(nil), y0), z2)) -> c1(MARK(first(from(nil), y0)))
   A__FIRST(s(z0), cons(first(from(s(y0)), y1), z2)) -> c1(MARK(first(from(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(cons(y0, y1)), y2), z2)) -> c1(MARK(first(from(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(y0), y1), z2)) -> c1(MARK(first(from(y0), y1)))
   A__FIRST(s(z0), cons(first(from(y0), 0), z2)) -> c1(MARK(first(from(y0), 0)))
   A__FIRST(s(z0), cons(first(from(y0), nil), z2)) -> c1(MARK(first(from(y0), nil)))
   A__FIRST(s(z0), cons(first(from(y0), s(y1)), z2)) -> c1(MARK(first(from(y0), s(y1))))
   A__FIRST(s(z0), cons(first(s(first(y0, y1)), y2), z2)) -> c1(MARK(first(s(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(from(y0)), y1), z2)) -> c1(MARK(first(s(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(0), y0), z2)) -> c1(MARK(first(s(0), y0)))
   A__FIRST(s(z0), cons(first(s(nil), y0), z2)) -> c1(MARK(first(s(nil), y0)))
   A__FIRST(s(z0), cons(first(s(s(y0)), y1), z2)) -> c1(MARK(first(s(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(cons(y0, y1)), y2), z2)) -> c1(MARK(first(s(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(y0), y1), z2)) -> c1(MARK(first(s(y0), y1)))
   A__FIRST(s(z0), cons(first(s(y0), 0), z2)) -> c1(MARK(first(s(y0), 0)))
   A__FIRST(s(z0), cons(first(s(y0), nil), z2)) -> c1(MARK(first(s(y0), nil)))
   A__FIRST(s(z0), cons(first(s(y0), s(y1)), z2)) -> c1(MARK(first(s(y0), s(y1))))
   A__FIRST(s(z0), cons(first(0, first(y0, y1)), z2)) -> c1(MARK(first(0, first(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, first(y0, y1)), z2)) -> c1(MARK(first(nil, first(y0, y1))))
   A__FIRST(s(z0), cons(first(0, from(y0)), z2)) -> c1(MARK(first(0, from(y0))))
   A__FIRST(s(z0), cons(first(nil, from(y0)), z2)) -> c1(MARK(first(nil, from(y0))))
   A__FIRST(s(z0), cons(first(y0, cons(y1, y2)), z2)) -> c1(MARK(first(y0, cons(y1, y2))))
   A__FIRST(s(z0), cons(first(0, cons(y0, y1)), z2)) -> c1(MARK(first(0, cons(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, cons(y0, y1)), z2)) -> c1(MARK(first(nil, cons(y0, y1))))
   MARK(first(x0, cons(0, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c6(MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(MARK(cons(nil, x2)))
   A__FROM(from(y0)) -> c3(MARK(from(y0)))
   A__FROM(s(y0)) -> c3(MARK(s(y0)))
   A__FROM(cons(y0, y1)) -> c3(MARK(cons(y0, y1)))
   A__FROM(first(y0, 0)) -> c3(MARK(first(y0, 0)))
   A__FROM(first(y0, nil)) -> c3(MARK(first(y0, nil)))
   A__FROM(first(y0, s(y1))) -> c3(MARK(first(y0, s(y1))))
   A__FROM(first(cons(y0, y1), y2)) -> c3(MARK(first(cons(y0, y1), y2)))
   A__FROM(first(0, y0)) -> c3(MARK(first(0, y0)))
   A__FROM(first(nil, y0)) -> c3(MARK(first(nil, y0)))
   A__FROM(first(y0, first(y1, first(y2, y3)))) -> c3(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FROM(first(y0, first(y1, from(y2)))) -> c3(MARK(first(y0, first(y1, from(y2)))))
   A__FROM(first(y0, first(y1, 0))) -> c3(MARK(first(y0, first(y1, 0))))
   A__FROM(first(y0, first(y1, nil))) -> c3(MARK(first(y0, first(y1, nil))))
   A__FROM(first(y0, first(y1, s(y2)))) -> c3(MARK(first(y0, first(y1, s(y2)))))
   A__FROM(first(y0, first(y1, cons(y2, y3)))) -> c3(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FROM(first(y0, first(first(y1, y2), y3))) -> c3(MARK(first(y0, first(first(y1, y2), y3))))
   A__FROM(first(y0, first(from(y1), y2))) -> c3(MARK(first(y0, first(from(y1), y2))))
   A__FROM(first(y0, first(0, y1))) -> c3(MARK(first(y0, first(0, y1))))
   A__FROM(first(y0, first(nil, y1))) -> c3(MARK(first(y0, first(nil, y1))))
   A__FROM(first(y0, first(s(y1), y2))) -> c3(MARK(first(y0, first(s(y1), y2))))
   A__FROM(first(y0, first(cons(y1, y2), y3))) -> c3(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), first(y2, y3))) -> c3(MARK(first(first(y0, y1), first(y2, y3))))
   A__FROM(first(from(y0), first(y1, y2))) -> c3(MARK(first(from(y0), first(y1, y2))))
   A__FROM(first(s(y0), first(y1, y2))) -> c3(MARK(first(s(y0), first(y1, y2))))
   A__FROM(first(y0, first(y1, y2))) -> c3(MARK(first(y0, first(y1, y2))))
   A__FROM(first(cons(y0, y1), first(y2, y3))) -> c3(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FROM(first(y0, from(y1))) -> c3(MARK(first(y0, from(y1))))
   A__FROM(first(y0, from(first(y1, y2)))) -> c3(MARK(first(y0, from(first(y1, y2)))))
   A__FROM(first(y0, from(from(y1)))) -> c3(MARK(first(y0, from(from(y1)))))
   A__FROM(first(y0, from(0))) -> c3(MARK(first(y0, from(0))))
   A__FROM(first(y0, from(nil))) -> c3(MARK(first(y0, from(nil))))
   A__FROM(first(y0, from(s(y1)))) -> c3(MARK(first(y0, from(s(y1)))))
   A__FROM(first(y0, from(cons(y1, y2)))) -> c3(MARK(first(y0, from(cons(y1, y2)))))
   A__FROM(first(first(y0, y1), from(y2))) -> c3(MARK(first(first(y0, y1), from(y2))))
   A__FROM(first(from(y0), from(y1))) -> c3(MARK(first(from(y0), from(y1))))
   A__FROM(first(s(y0), from(y1))) -> c3(MARK(first(s(y0), from(y1))))
   A__FROM(first(cons(y0, y1), from(y2))) -> c3(MARK(first(cons(y0, y1), from(y2))))
   A__FROM(first(y0, cons(first(y1, y2), y3))) -> c3(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FROM(first(y0, cons(from(y1), y2))) -> c3(MARK(first(y0, cons(from(y1), y2))))
   A__FROM(first(y0, cons(s(y1), y2))) -> c3(MARK(first(y0, cons(s(y1), y2))))
   A__FROM(first(y0, cons(cons(y1, y2), y3))) -> c3(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), cons(y2, y3))) -> c3(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FROM(first(from(y0), cons(y1, y2))) -> c3(MARK(first(from(y0), cons(y1, y2))))
   A__FROM(first(s(y0), cons(y1, y2))) -> c3(MARK(first(s(y0), cons(y1, y2))))
   A__FROM(first(cons(y0, y1), cons(y2, y3))) -> c3(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FROM(first(first(y0, first(y1, y2)), y3)) -> c3(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FROM(first(first(y0, from(y1)), y2)) -> c3(MARK(first(first(y0, from(y1)), y2)))
   A__FROM(first(first(y0, 0), y1)) -> c3(MARK(first(first(y0, 0), y1)))
   A__FROM(first(first(y0, nil), y1)) -> c3(MARK(first(first(y0, nil), y1)))
   A__FROM(first(first(y0, s(y1)), y2)) -> c3(MARK(first(first(y0, s(y1)), y2)))
   A__FROM(first(first(y0, cons(y1, y2)), y3)) -> c3(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FROM(first(first(first(y0, y1), y2), y3)) -> c3(MARK(first(first(first(y0, y1), y2), y3)))
   A__FROM(first(first(from(y0), y1), y2)) -> c3(MARK(first(first(from(y0), y1), y2)))
   A__FROM(first(first(0, y0), y1)) -> c3(MARK(first(first(0, y0), y1)))
   A__FROM(first(first(nil, y0), y1)) -> c3(MARK(first(first(nil, y0), y1)))
   A__FROM(first(first(s(y0), y1), y2)) -> c3(MARK(first(first(s(y0), y1), y2)))
   A__FROM(first(first(cons(y0, y1), y2), y3)) -> c3(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FROM(first(first(y0, y1), 0)) -> c3(MARK(first(first(y0, y1), 0)))
   A__FROM(first(first(y0, y1), nil)) -> c3(MARK(first(first(y0, y1), nil)))
   A__FROM(first(first(y0, y1), s(y2))) -> c3(MARK(first(first(y0, y1), s(y2))))
   A__FROM(first(first(y0, y1), y2)) -> c3(MARK(first(first(y0, y1), y2)))
   A__FROM(first(from(first(y0, y1)), y2)) -> c3(MARK(first(from(first(y0, y1)), y2)))
   A__FROM(first(from(from(y0)), y1)) -> c3(MARK(first(from(from(y0)), y1)))
   A__FROM(first(from(0), y0)) -> c3(MARK(first(from(0), y0)))
   A__FROM(first(from(nil), y0)) -> c3(MARK(first(from(nil), y0)))
   A__FROM(first(from(s(y0)), y1)) -> c3(MARK(first(from(s(y0)), y1)))
   A__FROM(first(from(cons(y0, y1)), y2)) -> c3(MARK(first(from(cons(y0, y1)), y2)))
   A__FROM(first(from(y0), y1)) -> c3(MARK(first(from(y0), y1)))
   A__FROM(first(from(y0), 0)) -> c3(MARK(first(from(y0), 0)))
   A__FROM(first(from(y0), nil)) -> c3(MARK(first(from(y0), nil)))
   A__FROM(first(from(y0), s(y1))) -> c3(MARK(first(from(y0), s(y1))))
   A__FROM(first(s(first(y0, y1)), y2)) -> c3(MARK(first(s(first(y0, y1)), y2)))
   A__FROM(first(s(from(y0)), y1)) -> c3(MARK(first(s(from(y0)), y1)))
   A__FROM(first(s(0), y0)) -> c3(MARK(first(s(0), y0)))
   A__FROM(first(s(nil), y0)) -> c3(MARK(first(s(nil), y0)))
   A__FROM(first(s(s(y0)), y1)) -> c3(MARK(first(s(s(y0)), y1)))
   A__FROM(first(s(cons(y0, y1)), y2)) -> c3(MARK(first(s(cons(y0, y1)), y2)))
   A__FROM(first(s(y0), y1)) -> c3(MARK(first(s(y0), y1)))
   A__FROM(first(s(y0), 0)) -> c3(MARK(first(s(y0), 0)))
   A__FROM(first(s(y0), nil)) -> c3(MARK(first(s(y0), nil)))
   A__FROM(first(s(y0), s(y1))) -> c3(MARK(first(s(y0), s(y1))))
   A__FROM(first(0, first(y0, y1))) -> c3(MARK(first(0, first(y0, y1))))
   A__FROM(first(nil, first(y0, y1))) -> c3(MARK(first(nil, first(y0, y1))))
   A__FROM(first(0, from(y0))) -> c3(MARK(first(0, from(y0))))
   A__FROM(first(nil, from(y0))) -> c3(MARK(first(nil, from(y0))))
   A__FROM(first(y0, cons(y1, y2))) -> c3(MARK(first(y0, cons(y1, y2))))
   A__FROM(first(0, cons(y0, y1))) -> c3(MARK(first(0, cons(y0, y1))))
   A__FROM(first(nil, cons(y0, y1))) -> c3(MARK(first(nil, cons(y0, y1))))
   A__FROM(first(y0, cons(0, y1))) -> c3(MARK(first(y0, cons(0, y1))))
   A__FROM(first(y0, cons(nil, y1))) -> c3(MARK(first(y0, cons(nil, y1))))
   MARK(from(s(z0))) -> c7(A__FROM(s(mark(z0))), MARK(s(z0)))
   MARK(from(cons(z0, z1))) -> c7(A__FROM(cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)))
   MARK(from(first(x0, x1))) -> c7(A__FROM(first(mark(x0), mark(x1))), MARK(first(x0, x1)))
   MARK(from(first(x0, first(z0, z1)))) -> c7(A__FROM(a__first(mark(x0), a__first(mark(z0), mark(z1)))), MARK(first(x0, first(z0, z1))))
   MARK(from(first(x0, from(z0)))) -> c7(A__FROM(a__first(mark(x0), a__from(mark(z0)))), MARK(first(x0, from(z0))))
   MARK(from(first(x0, 0))) -> c7(A__FROM(a__first(mark(x0), 0)), MARK(first(x0, 0)))
   MARK(from(first(x0, nil))) -> c7(A__FROM(a__first(mark(x0), nil)), MARK(first(x0, nil)))
   MARK(from(first(x0, s(z0)))) -> c7(A__FROM(a__first(mark(x0), s(mark(z0)))), MARK(first(x0, s(z0))))
   MARK(from(first(x0, cons(z0, z1)))) -> c7(A__FROM(a__first(mark(x0), cons(mark(z0), z1))), MARK(first(x0, cons(z0, z1))))
   MARK(from(first(first(z0, z1), x1))) -> c7(A__FROM(a__first(a__first(mark(z0), mark(z1)), mark(x1))), MARK(first(first(z0, z1), x1)))
   MARK(from(first(from(z0), x1))) -> c7(A__FROM(a__first(a__from(mark(z0)), mark(x1))), MARK(first(from(z0), x1)))
   MARK(from(first(0, x1))) -> c7(A__FROM(a__first(0, mark(x1))), MARK(first(0, x1)))
   MARK(from(first(nil, x1))) -> c7(A__FROM(a__first(nil, mark(x1))), MARK(first(nil, x1)))
   MARK(from(first(s(z0), x1))) -> c7(A__FROM(a__first(s(mark(z0)), mark(x1))), MARK(first(s(z0), x1)))
   MARK(from(first(cons(z0, z1), x1))) -> c7(A__FROM(a__first(cons(mark(z0), z1), mark(x1))), MARK(first(cons(z0, z1), x1)))
   MARK(from(from(x0))) -> c7(A__FROM(cons(mark(mark(x0)), from(s(mark(x0))))), MARK(from(x0)))
   MARK(from(from(x0))) -> c7(A__FROM(from(mark(x0))), MARK(from(x0)))
   MARK(from(from(first(z0, z1)))) -> c7(A__FROM(a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(from(from(from(z0)))) -> c7(A__FROM(a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(from(from(s(z0)))) -> c7(A__FROM(a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(from(from(cons(z0, z1)))) -> c7(A__FROM(a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(from(from(0))) -> c7(A__FROM(a__from(0)))
   MARK(from(from(nil))) -> c7(A__FROM(a__from(nil)))
   MARK(s(s(y0))) -> c10(MARK(s(y0)))
   MARK(s(cons(y0, y1))) -> c10(MARK(cons(y0, y1)))
   MARK(s(first(y0, 0))) -> c10(MARK(first(y0, 0)))
   MARK(s(first(y0, nil))) -> c10(MARK(first(y0, nil)))
   MARK(s(first(y0, s(y1)))) -> c10(MARK(first(y0, s(y1))))
   MARK(s(first(cons(y0, y1), y2))) -> c10(MARK(first(cons(y0, y1), y2)))
   MARK(s(first(0, y0))) -> c10(MARK(first(0, y0)))
   MARK(s(first(nil, y0))) -> c10(MARK(first(nil, y0)))
   MARK(s(first(y0, first(y1, first(y2, y3))))) -> c10(MARK(first(y0, first(y1, first(y2, y3)))))
   MARK(s(first(y0, first(y1, from(y2))))) -> c10(MARK(first(y0, first(y1, from(y2)))))
   MARK(s(first(y0, first(y1, 0)))) -> c10(MARK(first(y0, first(y1, 0))))
   MARK(s(first(y0, first(y1, nil)))) -> c10(MARK(first(y0, first(y1, nil))))
   MARK(s(first(y0, first(y1, s(y2))))) -> c10(MARK(first(y0, first(y1, s(y2)))))
   MARK(s(first(y0, first(y1, cons(y2, y3))))) -> c10(MARK(first(y0, first(y1, cons(y2, y3)))))
   MARK(s(first(y0, first(first(y1, y2), y3)))) -> c10(MARK(first(y0, first(first(y1, y2), y3))))
   MARK(s(first(y0, first(from(y1), y2)))) -> c10(MARK(first(y0, first(from(y1), y2))))
   MARK(s(first(y0, first(0, y1)))) -> c10(MARK(first(y0, first(0, y1))))
   MARK(s(first(y0, first(nil, y1)))) -> c10(MARK(first(y0, first(nil, y1))))
   MARK(s(first(y0, first(s(y1), y2)))) -> c10(MARK(first(y0, first(s(y1), y2))))
   MARK(s(first(y0, first(cons(y1, y2), y3)))) -> c10(MARK(first(y0, first(cons(y1, y2), y3))))
   MARK(s(first(first(y0, y1), first(y2, y3)))) -> c10(MARK(first(first(y0, y1), first(y2, y3))))
   MARK(s(first(from(y0), first(y1, y2)))) -> c10(MARK(first(from(y0), first(y1, y2))))
   MARK(s(first(s(y0), first(y1, y2)))) -> c10(MARK(first(s(y0), first(y1, y2))))
   MARK(s(first(y0, first(y1, y2)))) -> c10(MARK(first(y0, first(y1, y2))))
   MARK(s(first(cons(y0, y1), first(y2, y3)))) -> c10(MARK(first(cons(y0, y1), first(y2, y3))))
   MARK(s(first(y0, from(y1)))) -> c10(MARK(first(y0, from(y1))))
   MARK(s(first(y0, from(first(y1, y2))))) -> c10(MARK(first(y0, from(first(y1, y2)))))
   MARK(s(first(y0, from(from(y1))))) -> c10(MARK(first(y0, from(from(y1)))))
   MARK(s(first(y0, from(0)))) -> c10(MARK(first(y0, from(0))))
   MARK(s(first(y0, from(nil)))) -> c10(MARK(first(y0, from(nil))))
   MARK(s(first(y0, from(s(y1))))) -> c10(MARK(first(y0, from(s(y1)))))
   MARK(s(first(y0, from(cons(y1, y2))))) -> c10(MARK(first(y0, from(cons(y1, y2)))))
   MARK(s(first(first(y0, y1), from(y2)))) -> c10(MARK(first(first(y0, y1), from(y2))))
   MARK(s(first(from(y0), from(y1)))) -> c10(MARK(first(from(y0), from(y1))))
   MARK(s(first(s(y0), from(y1)))) -> c10(MARK(first(s(y0), from(y1))))
   MARK(s(first(cons(y0, y1), from(y2)))) -> c10(MARK(first(cons(y0, y1), from(y2))))
   MARK(s(first(y0, cons(first(y1, y2), y3)))) -> c10(MARK(first(y0, cons(first(y1, y2), y3))))
   MARK(s(first(y0, cons(from(y1), y2)))) -> c10(MARK(first(y0, cons(from(y1), y2))))
   MARK(s(first(y0, cons(s(y1), y2)))) -> c10(MARK(first(y0, cons(s(y1), y2))))
   MARK(s(first(y0, cons(cons(y1, y2), y3)))) -> c10(MARK(first(y0, cons(cons(y1, y2), y3))))
   MARK(s(first(first(y0, y1), cons(y2, y3)))) -> c10(MARK(first(first(y0, y1), cons(y2, y3))))
   MARK(s(first(from(y0), cons(y1, y2)))) -> c10(MARK(first(from(y0), cons(y1, y2))))
   MARK(s(first(s(y0), cons(y1, y2)))) -> c10(MARK(first(s(y0), cons(y1, y2))))
   MARK(s(first(cons(y0, y1), cons(y2, y3)))) -> c10(MARK(first(cons(y0, y1), cons(y2, y3))))
   MARK(s(first(first(y0, first(y1, y2)), y3))) -> c10(MARK(first(first(y0, first(y1, y2)), y3)))
   MARK(s(first(first(y0, from(y1)), y2))) -> c10(MARK(first(first(y0, from(y1)), y2)))
   MARK(s(first(first(y0, 0), y1))) -> c10(MARK(first(first(y0, 0), y1)))
   MARK(s(first(first(y0, nil), y1))) -> c10(MARK(first(first(y0, nil), y1)))
   MARK(s(first(first(y0, s(y1)), y2))) -> c10(MARK(first(first(y0, s(y1)), y2)))
   MARK(s(first(first(y0, cons(y1, y2)), y3))) -> c10(MARK(first(first(y0, cons(y1, y2)), y3)))
   MARK(s(first(first(first(y0, y1), y2), y3))) -> c10(MARK(first(first(first(y0, y1), y2), y3)))
   MARK(s(first(first(from(y0), y1), y2))) -> c10(MARK(first(first(from(y0), y1), y2)))
   MARK(s(first(first(0, y0), y1))) -> c10(MARK(first(first(0, y0), y1)))
   MARK(s(first(first(nil, y0), y1))) -> c10(MARK(first(first(nil, y0), y1)))
   MARK(s(first(first(s(y0), y1), y2))) -> c10(MARK(first(first(s(y0), y1), y2)))
   MARK(s(first(first(cons(y0, y1), y2), y3))) -> c10(MARK(first(first(cons(y0, y1), y2), y3)))
   MARK(s(first(first(y0, y1), 0))) -> c10(MARK(first(first(y0, y1), 0)))
   MARK(s(first(first(y0, y1), nil))) -> c10(MARK(first(first(y0, y1), nil)))
   MARK(s(first(first(y0, y1), s(y2)))) -> c10(MARK(first(first(y0, y1), s(y2))))
   MARK(s(first(first(y0, y1), y2))) -> c10(MARK(first(first(y0, y1), y2)))
   MARK(s(first(from(first(y0, y1)), y2))) -> c10(MARK(first(from(first(y0, y1)), y2)))
   MARK(s(first(from(from(y0)), y1))) -> c10(MARK(first(from(from(y0)), y1)))
   MARK(s(first(from(s(y0)), y1))) -> c10(MARK(first(from(s(y0)), y1)))
   MARK(s(first(from(cons(y0, y1)), y2))) -> c10(MARK(first(from(cons(y0, y1)), y2)))
   MARK(s(first(from(y0), y1))) -> c10(MARK(first(from(y0), y1)))
   MARK(s(first(from(y0), 0))) -> c10(MARK(first(from(y0), 0)))
   MARK(s(first(from(y0), nil))) -> c10(MARK(first(from(y0), nil)))
   MARK(s(first(from(y0), s(y1)))) -> c10(MARK(first(from(y0), s(y1))))
   MARK(s(first(s(first(y0, y1)), y2))) -> c10(MARK(first(s(first(y0, y1)), y2)))
   MARK(s(first(s(from(y0)), y1))) -> c10(MARK(first(s(from(y0)), y1)))
   MARK(s(first(s(0), y0))) -> c10(MARK(first(s(0), y0)))
   MARK(s(first(s(nil), y0))) -> c10(MARK(first(s(nil), y0)))
   MARK(s(first(s(s(y0)), y1))) -> c10(MARK(first(s(s(y0)), y1)))
   MARK(s(first(s(cons(y0, y1)), y2))) -> c10(MARK(first(s(cons(y0, y1)), y2)))
   MARK(s(first(s(y0), y1))) -> c10(MARK(first(s(y0), y1)))
   MARK(s(first(s(y0), 0))) -> c10(MARK(first(s(y0), 0)))
   MARK(s(first(s(y0), nil))) -> c10(MARK(first(s(y0), nil)))
   MARK(s(first(s(y0), s(y1)))) -> c10(MARK(first(s(y0), s(y1))))
   MARK(s(first(0, first(y0, y1)))) -> c10(MARK(first(0, first(y0, y1))))
   MARK(s(first(nil, first(y0, y1)))) -> c10(MARK(first(nil, first(y0, y1))))
   MARK(s(first(0, from(y0)))) -> c10(MARK(first(0, from(y0))))
   MARK(s(first(nil, from(y0)))) -> c10(MARK(first(nil, from(y0))))
   MARK(s(first(y0, cons(y1, y2)))) -> c10(MARK(first(y0, cons(y1, y2))))
   MARK(s(first(0, cons(y0, y1)))) -> c10(MARK(first(0, cons(y0, y1))))
   MARK(s(first(nil, cons(y0, y1)))) -> c10(MARK(first(nil, cons(y0, y1))))
   MARK(s(first(from(0), y0))) -> c10(MARK(first(from(0), y0)))
   MARK(s(first(from(nil), y0))) -> c10(MARK(first(from(nil), y0)))
   MARK(s(first(y0, cons(0, y1)))) -> c10(MARK(first(y0, cons(0, y1))))
   MARK(s(first(y0, cons(nil, y1)))) -> c10(MARK(first(y0, cons(nil, y1))))
   MARK(s(from(s(y0)))) -> c10(MARK(from(s(y0))))
   MARK(s(from(cons(y0, y1)))) -> c10(MARK(from(cons(y0, y1))))
   MARK(s(from(first(y0, y1)))) -> c10(MARK(from(first(y0, y1))))
   MARK(s(from(first(y0, first(y1, y2))))) -> c10(MARK(from(first(y0, first(y1, y2)))))
   MARK(s(from(first(y0, from(y1))))) -> c10(MARK(from(first(y0, from(y1)))))
   MARK(s(from(first(y0, 0)))) -> c10(MARK(from(first(y0, 0))))
   MARK(s(from(first(y0, nil)))) -> c10(MARK(from(first(y0, nil))))
   MARK(s(from(first(y0, s(y1))))) -> c10(MARK(from(first(y0, s(y1)))))
   MARK(s(from(first(y0, cons(y1, y2))))) -> c10(MARK(from(first(y0, cons(y1, y2)))))
   MARK(s(from(first(first(y0, y1), y2)))) -> c10(MARK(from(first(first(y0, y1), y2))))
   MARK(s(from(first(from(y0), y1)))) -> c10(MARK(from(first(from(y0), y1))))
   MARK(s(from(first(0, y0)))) -> c10(MARK(from(first(0, y0))))
   MARK(s(from(first(nil, y0)))) -> c10(MARK(from(first(nil, y0))))
   MARK(s(from(first(s(y0), y1)))) -> c10(MARK(from(first(s(y0), y1))))
   MARK(s(from(first(cons(y0, y1), y2)))) -> c10(MARK(from(first(cons(y0, y1), y2))))
   MARK(s(from(from(y0)))) -> c10(MARK(from(from(y0))))
   MARK(s(from(from(first(y0, y1))))) -> c10(MARK(from(from(first(y0, y1)))))
   MARK(s(from(from(from(y0))))) -> c10(MARK(from(from(from(y0)))))
   MARK(s(from(from(s(y0))))) -> c10(MARK(from(from(s(y0)))))
   MARK(s(from(from(cons(y0, y1))))) -> c10(MARK(from(from(cons(y0, y1)))))
   MARK(s(from(from(0)))) -> c10(MARK(from(from(0))))
   MARK(s(from(from(nil)))) -> c10(MARK(from(from(nil))))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   MARK_1, A__FIRST_2, A__FROM_1

Compound Symbols:   c11_1, c5_1, c6_1, c5_2, c6_2, c1_1, c3_1, c7_2, c7_1, c10_1


----------------------------------------

(117) CdtRhsSimplificationProcessorProof (BOTH BOUNDS(ID, ID))
Removed 2 trailing tuple parts
----------------------------------------

(118)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
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   MARK(s(first(first(y0, first(y1, y2)), y3))) -> c10(MARK(first(first(y0, first(y1, y2)), y3)))
   MARK(s(first(first(y0, from(y1)), y2))) -> c10(MARK(first(first(y0, from(y1)), y2)))
   MARK(s(first(first(y0, 0), y1))) -> c10(MARK(first(first(y0, 0), y1)))
   MARK(s(first(first(y0, nil), y1))) -> c10(MARK(first(first(y0, nil), y1)))
   MARK(s(first(first(y0, s(y1)), y2))) -> c10(MARK(first(first(y0, s(y1)), y2)))
   MARK(s(first(first(y0, cons(y1, y2)), y3))) -> c10(MARK(first(first(y0, cons(y1, y2)), y3)))
   MARK(s(first(first(first(y0, y1), y2), y3))) -> c10(MARK(first(first(first(y0, y1), y2), y3)))
   MARK(s(first(first(from(y0), y1), y2))) -> c10(MARK(first(first(from(y0), y1), y2)))
   MARK(s(first(first(0, y0), y1))) -> c10(MARK(first(first(0, y0), y1)))
   MARK(s(first(first(nil, y0), y1))) -> c10(MARK(first(first(nil, y0), y1)))
   MARK(s(first(first(s(y0), y1), y2))) -> c10(MARK(first(first(s(y0), y1), y2)))
   MARK(s(first(first(cons(y0, y1), y2), y3))) -> c10(MARK(first(first(cons(y0, y1), y2), y3)))
   MARK(s(first(first(y0, y1), 0))) -> c10(MARK(first(first(y0, y1), 0)))
   MARK(s(first(first(y0, y1), nil))) -> c10(MARK(first(first(y0, y1), nil)))
   MARK(s(first(first(y0, y1), s(y2)))) -> c10(MARK(first(first(y0, y1), s(y2))))
   MARK(s(first(first(y0, y1), y2))) -> c10(MARK(first(first(y0, y1), y2)))
   MARK(s(first(from(first(y0, y1)), y2))) -> c10(MARK(first(from(first(y0, y1)), y2)))
   MARK(s(first(from(from(y0)), y1))) -> c10(MARK(first(from(from(y0)), y1)))
   MARK(s(first(from(s(y0)), y1))) -> c10(MARK(first(from(s(y0)), y1)))
   MARK(s(first(from(cons(y0, y1)), y2))) -> c10(MARK(first(from(cons(y0, y1)), y2)))
   MARK(s(first(from(y0), y1))) -> c10(MARK(first(from(y0), y1)))
   MARK(s(first(from(y0), 0))) -> c10(MARK(first(from(y0), 0)))
   MARK(s(first(from(y0), nil))) -> c10(MARK(first(from(y0), nil)))
   MARK(s(first(from(y0), s(y1)))) -> c10(MARK(first(from(y0), s(y1))))
   MARK(s(first(s(first(y0, y1)), y2))) -> c10(MARK(first(s(first(y0, y1)), y2)))
   MARK(s(first(s(from(y0)), y1))) -> c10(MARK(first(s(from(y0)), y1)))
   MARK(s(first(s(0), y0))) -> c10(MARK(first(s(0), y0)))
   MARK(s(first(s(nil), y0))) -> c10(MARK(first(s(nil), y0)))
   MARK(s(first(s(s(y0)), y1))) -> c10(MARK(first(s(s(y0)), y1)))
   MARK(s(first(s(cons(y0, y1)), y2))) -> c10(MARK(first(s(cons(y0, y1)), y2)))
   MARK(s(first(s(y0), y1))) -> c10(MARK(first(s(y0), y1)))
   MARK(s(first(s(y0), 0))) -> c10(MARK(first(s(y0), 0)))
   MARK(s(first(s(y0), nil))) -> c10(MARK(first(s(y0), nil)))
   MARK(s(first(s(y0), s(y1)))) -> c10(MARK(first(s(y0), s(y1))))
   MARK(s(first(0, first(y0, y1)))) -> c10(MARK(first(0, first(y0, y1))))
   MARK(s(first(nil, first(y0, y1)))) -> c10(MARK(first(nil, first(y0, y1))))
   MARK(s(first(0, from(y0)))) -> c10(MARK(first(0, from(y0))))
   MARK(s(first(nil, from(y0)))) -> c10(MARK(first(nil, from(y0))))
   MARK(s(first(y0, cons(y1, y2)))) -> c10(MARK(first(y0, cons(y1, y2))))
   MARK(s(first(0, cons(y0, y1)))) -> c10(MARK(first(0, cons(y0, y1))))
   MARK(s(first(nil, cons(y0, y1)))) -> c10(MARK(first(nil, cons(y0, y1))))
   MARK(s(first(from(0), y0))) -> c10(MARK(first(from(0), y0)))
   MARK(s(first(from(nil), y0))) -> c10(MARK(first(from(nil), y0)))
   MARK(s(first(y0, cons(0, y1)))) -> c10(MARK(first(y0, cons(0, y1))))
   MARK(s(first(y0, cons(nil, y1)))) -> c10(MARK(first(y0, cons(nil, y1))))
   MARK(s(from(s(y0)))) -> c10(MARK(from(s(y0))))
   MARK(s(from(cons(y0, y1)))) -> c10(MARK(from(cons(y0, y1))))
   MARK(s(from(first(y0, y1)))) -> c10(MARK(from(first(y0, y1))))
   MARK(s(from(first(y0, first(y1, y2))))) -> c10(MARK(from(first(y0, first(y1, y2)))))
   MARK(s(from(first(y0, from(y1))))) -> c10(MARK(from(first(y0, from(y1)))))
   MARK(s(from(first(y0, 0)))) -> c10(MARK(from(first(y0, 0))))
   MARK(s(from(first(y0, nil)))) -> c10(MARK(from(first(y0, nil))))
   MARK(s(from(first(y0, s(y1))))) -> c10(MARK(from(first(y0, s(y1)))))
   MARK(s(from(first(y0, cons(y1, y2))))) -> c10(MARK(from(first(y0, cons(y1, y2)))))
   MARK(s(from(first(first(y0, y1), y2)))) -> c10(MARK(from(first(first(y0, y1), y2))))
   MARK(s(from(first(from(y0), y1)))) -> c10(MARK(from(first(from(y0), y1))))
   MARK(s(from(first(0, y0)))) -> c10(MARK(from(first(0, y0))))
   MARK(s(from(first(nil, y0)))) -> c10(MARK(from(first(nil, y0))))
   MARK(s(from(first(s(y0), y1)))) -> c10(MARK(from(first(s(y0), y1))))
   MARK(s(from(first(cons(y0, y1), y2)))) -> c10(MARK(from(first(cons(y0, y1), y2))))
   MARK(s(from(from(y0)))) -> c10(MARK(from(from(y0))))
   MARK(s(from(from(first(y0, y1))))) -> c10(MARK(from(from(first(y0, y1)))))
   MARK(s(from(from(from(y0))))) -> c10(MARK(from(from(from(y0)))))
   MARK(s(from(from(s(y0))))) -> c10(MARK(from(from(s(y0)))))
   MARK(s(from(from(cons(y0, y1))))) -> c10(MARK(from(from(cons(y0, y1)))))
   MARK(s(from(from(0)))) -> c10(MARK(from(from(0))))
   MARK(s(from(from(nil)))) -> c10(MARK(from(from(nil))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)))
S tuples:
   MARK(cons(z0, z1)) -> c11(MARK(z0))
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, x1), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(first(x0, x1), x2)) -> c6(MARK(x2))
   MARK(first(from(first(z0, z1)), x1)) -> c6(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(from(from(z0)), x1)) -> c6(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(0), x1)) -> c6(A__FIRST(a__from(0), mark(x1)), MARK(x1))
   MARK(first(from(nil), x1)) -> c6(A__FIRST(a__from(nil), mark(x1)), MARK(x1))
   MARK(first(from(s(z0)), x1)) -> c6(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(cons(z0, z1)), x1)) -> c6(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(x1))
   MARK(first(from(x0), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(from(x0), x1)) -> c6(MARK(x1))
   MARK(first(s(first(z0, z1)), x1)) -> c6(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(s(from(z0)), x1)) -> c6(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(0), x1)) -> c6(A__FIRST(s(0), mark(x1)), MARK(x1))
   MARK(first(s(nil), x1)) -> c6(A__FIRST(s(nil), mark(x1)), MARK(x1))
   MARK(first(s(s(z0)), x1)) -> c6(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(cons(z0, z1)), x1)) -> c6(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(x1))
   MARK(first(s(x0), s(z0))) -> c6(MARK(s(z0)))
   A__FIRST(s(z0), cons(from(y0), z2)) -> c1(MARK(from(y0)))
   A__FIRST(s(z0), cons(s(y0), z2)) -> c1(MARK(s(y0)))
   A__FIRST(s(z0), cons(cons(y0, y1), z2)) -> c1(MARK(cons(y0, y1)))
   A__FIRST(s(z0), cons(first(y0, 0), z2)) -> c1(MARK(first(y0, 0)))
   A__FIRST(s(z0), cons(first(y0, nil), z2)) -> c1(MARK(first(y0, nil)))
   A__FIRST(s(z0), cons(first(y0, s(y1)), z2)) -> c1(MARK(first(y0, s(y1))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), y2), z2)) -> c1(MARK(first(cons(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(0, y0), z2)) -> c1(MARK(first(0, y0)))
   A__FIRST(s(z0), cons(first(nil, y0), z2)) -> c1(MARK(first(nil, y0)))
   A__FIRST(s(z0), cons(first(y0, first(y1, first(y2, y3))), z2)) -> c1(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FIRST(s(z0), cons(first(y0, first(y1, from(y2))), z2)) -> c1(MARK(first(y0, first(y1, from(y2)))))
   A__FIRST(s(z0), cons(first(y0, first(y1, 0)), z2)) -> c1(MARK(first(y0, first(y1, 0))))
   A__FIRST(s(z0), cons(first(y0, first(y1, nil)), z2)) -> c1(MARK(first(y0, first(y1, nil))))
   A__FIRST(s(z0), cons(first(y0, first(y1, s(y2))), z2)) -> c1(MARK(first(y0, first(y1, s(y2)))))
   A__FIRST(s(z0), cons(first(y0, first(y1, cons(y2, y3))), z2)) -> c1(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FIRST(s(z0), cons(first(y0, first(first(y1, y2), y3)), z2)) -> c1(MARK(first(y0, first(first(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(y0, first(from(y1), y2)), z2)) -> c1(MARK(first(y0, first(from(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, first(0, y1)), z2)) -> c1(MARK(first(y0, first(0, y1))))
   A__FIRST(s(z0), cons(first(y0, first(nil, y1)), z2)) -> c1(MARK(first(y0, first(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, first(s(y1), y2)), z2)) -> c1(MARK(first(y0, first(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, first(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), first(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), first(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), first(y1, y2)), z2)) -> c1(MARK(first(from(y0), first(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), first(y1, y2)), z2)) -> c1(MARK(first(s(y0), first(y1, y2))))
   A__FIRST(s(z0), cons(first(y0, first(y1, y2)), z2)) -> c1(MARK(first(y0, first(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), first(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FIRST(s(z0), cons(first(y0, from(y1)), z2)) -> c1(MARK(first(y0, from(y1))))
   A__FIRST(s(z0), cons(first(y0, from(first(y1, y2))), z2)) -> c1(MARK(first(y0, from(first(y1, y2)))))
   A__FIRST(s(z0), cons(first(y0, from(from(y1))), z2)) -> c1(MARK(first(y0, from(from(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(0)), z2)) -> c1(MARK(first(y0, from(0))))
   A__FIRST(s(z0), cons(first(y0, from(nil)), z2)) -> c1(MARK(first(y0, from(nil))))
   A__FIRST(s(z0), cons(first(y0, from(s(y1))), z2)) -> c1(MARK(first(y0, from(s(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(cons(y1, y2))), z2)) -> c1(MARK(first(y0, from(cons(y1, y2)))))
   A__FIRST(s(z0), cons(first(first(y0, y1), from(y2)), z2)) -> c1(MARK(first(first(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(from(y0), from(y1)), z2)) -> c1(MARK(first(from(y0), from(y1))))
   A__FIRST(s(z0), cons(first(s(y0), from(y1)), z2)) -> c1(MARK(first(s(y0), from(y1))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), from(y2)), z2)) -> c1(MARK(first(cons(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(y0, cons(first(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(y0, cons(from(y1), y2)), z2)) -> c1(MARK(first(y0, cons(from(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(0, y1)), z2)) -> c1(MARK(first(y0, cons(0, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(nil, y1)), z2)) -> c1(MARK(first(y0, cons(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(s(y1), y2)), z2)) -> c1(MARK(first(y0, cons(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), cons(y1, y2)), z2)) -> c1(MARK(first(from(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), cons(y1, y2)), z2)) -> c1(MARK(first(s(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(first(y0, first(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(y0, from(y1)), y2), z2)) -> c1(MARK(first(first(y0, from(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, 0), y1), z2)) -> c1(MARK(first(first(y0, 0), y1)))
   A__FIRST(s(z0), cons(first(first(y0, nil), y1), z2)) -> c1(MARK(first(first(y0, nil), y1)))
   A__FIRST(s(z0), cons(first(first(y0, s(y1)), y2), z2)) -> c1(MARK(first(first(y0, s(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, cons(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(first(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(first(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(from(y0), y1), y2), z2)) -> c1(MARK(first(first(from(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(0, y0), y1), z2)) -> c1(MARK(first(first(0, y0), y1)))
   A__FIRST(s(z0), cons(first(first(nil, y0), y1), z2)) -> c1(MARK(first(first(nil, y0), y1)))
   A__FIRST(s(z0), cons(first(first(s(y0), y1), y2), z2)) -> c1(MARK(first(first(s(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(cons(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(y0, y1), 0), z2)) -> c1(MARK(first(first(y0, y1), 0)))
   A__FIRST(s(z0), cons(first(first(y0, y1), nil), z2)) -> c1(MARK(first(first(y0, y1), nil)))
   A__FIRST(s(z0), cons(first(first(y0, y1), s(y2)), z2)) -> c1(MARK(first(first(y0, y1), s(y2))))
   A__FIRST(s(z0), cons(first(first(y0, y1), y2), z2)) -> c1(MARK(first(first(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(from(first(y0, y1)), y2), z2)) -> c1(MARK(first(from(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(from(y0)), y1), z2)) -> c1(MARK(first(from(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(0), y0), z2)) -> c1(MARK(first(from(0), y0)))
   A__FIRST(s(z0), cons(first(from(nil), y0), z2)) -> c1(MARK(first(from(nil), y0)))
   A__FIRST(s(z0), cons(first(from(s(y0)), y1), z2)) -> c1(MARK(first(from(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(cons(y0, y1)), y2), z2)) -> c1(MARK(first(from(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(y0), y1), z2)) -> c1(MARK(first(from(y0), y1)))
   A__FIRST(s(z0), cons(first(from(y0), 0), z2)) -> c1(MARK(first(from(y0), 0)))
   A__FIRST(s(z0), cons(first(from(y0), nil), z2)) -> c1(MARK(first(from(y0), nil)))
   A__FIRST(s(z0), cons(first(from(y0), s(y1)), z2)) -> c1(MARK(first(from(y0), s(y1))))
   A__FIRST(s(z0), cons(first(s(first(y0, y1)), y2), z2)) -> c1(MARK(first(s(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(from(y0)), y1), z2)) -> c1(MARK(first(s(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(0), y0), z2)) -> c1(MARK(first(s(0), y0)))
   A__FIRST(s(z0), cons(first(s(nil), y0), z2)) -> c1(MARK(first(s(nil), y0)))
   A__FIRST(s(z0), cons(first(s(s(y0)), y1), z2)) -> c1(MARK(first(s(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(cons(y0, y1)), y2), z2)) -> c1(MARK(first(s(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(y0), y1), z2)) -> c1(MARK(first(s(y0), y1)))
   A__FIRST(s(z0), cons(first(s(y0), 0), z2)) -> c1(MARK(first(s(y0), 0)))
   A__FIRST(s(z0), cons(first(s(y0), nil), z2)) -> c1(MARK(first(s(y0), nil)))
   A__FIRST(s(z0), cons(first(s(y0), s(y1)), z2)) -> c1(MARK(first(s(y0), s(y1))))
   A__FIRST(s(z0), cons(first(0, first(y0, y1)), z2)) -> c1(MARK(first(0, first(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, first(y0, y1)), z2)) -> c1(MARK(first(nil, first(y0, y1))))
   A__FIRST(s(z0), cons(first(0, from(y0)), z2)) -> c1(MARK(first(0, from(y0))))
   A__FIRST(s(z0), cons(first(nil, from(y0)), z2)) -> c1(MARK(first(nil, from(y0))))
   A__FIRST(s(z0), cons(first(y0, cons(y1, y2)), z2)) -> c1(MARK(first(y0, cons(y1, y2))))
   A__FIRST(s(z0), cons(first(0, cons(y0, y1)), z2)) -> c1(MARK(first(0, cons(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, cons(y0, y1)), z2)) -> c1(MARK(first(nil, cons(y0, y1))))
   MARK(first(x0, cons(0, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c6(MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(MARK(cons(nil, x2)))
   A__FROM(from(y0)) -> c3(MARK(from(y0)))
   A__FROM(s(y0)) -> c3(MARK(s(y0)))
   A__FROM(cons(y0, y1)) -> c3(MARK(cons(y0, y1)))
   A__FROM(first(y0, 0)) -> c3(MARK(first(y0, 0)))
   A__FROM(first(y0, nil)) -> c3(MARK(first(y0, nil)))
   A__FROM(first(y0, s(y1))) -> c3(MARK(first(y0, s(y1))))
   A__FROM(first(cons(y0, y1), y2)) -> c3(MARK(first(cons(y0, y1), y2)))
   A__FROM(first(0, y0)) -> c3(MARK(first(0, y0)))
   A__FROM(first(nil, y0)) -> c3(MARK(first(nil, y0)))
   A__FROM(first(y0, first(y1, first(y2, y3)))) -> c3(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FROM(first(y0, first(y1, from(y2)))) -> c3(MARK(first(y0, first(y1, from(y2)))))
   A__FROM(first(y0, first(y1, 0))) -> c3(MARK(first(y0, first(y1, 0))))
   A__FROM(first(y0, first(y1, nil))) -> c3(MARK(first(y0, first(y1, nil))))
   A__FROM(first(y0, first(y1, s(y2)))) -> c3(MARK(first(y0, first(y1, s(y2)))))
   A__FROM(first(y0, first(y1, cons(y2, y3)))) -> c3(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FROM(first(y0, first(first(y1, y2), y3))) -> c3(MARK(first(y0, first(first(y1, y2), y3))))
   A__FROM(first(y0, first(from(y1), y2))) -> c3(MARK(first(y0, first(from(y1), y2))))
   A__FROM(first(y0, first(0, y1))) -> c3(MARK(first(y0, first(0, y1))))
   A__FROM(first(y0, first(nil, y1))) -> c3(MARK(first(y0, first(nil, y1))))
   A__FROM(first(y0, first(s(y1), y2))) -> c3(MARK(first(y0, first(s(y1), y2))))
   A__FROM(first(y0, first(cons(y1, y2), y3))) -> c3(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), first(y2, y3))) -> c3(MARK(first(first(y0, y1), first(y2, y3))))
   A__FROM(first(from(y0), first(y1, y2))) -> c3(MARK(first(from(y0), first(y1, y2))))
   A__FROM(first(s(y0), first(y1, y2))) -> c3(MARK(first(s(y0), first(y1, y2))))
   A__FROM(first(y0, first(y1, y2))) -> c3(MARK(first(y0, first(y1, y2))))
   A__FROM(first(cons(y0, y1), first(y2, y3))) -> c3(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FROM(first(y0, from(y1))) -> c3(MARK(first(y0, from(y1))))
   A__FROM(first(y0, from(first(y1, y2)))) -> c3(MARK(first(y0, from(first(y1, y2)))))
   A__FROM(first(y0, from(from(y1)))) -> c3(MARK(first(y0, from(from(y1)))))
   A__FROM(first(y0, from(0))) -> c3(MARK(first(y0, from(0))))
   A__FROM(first(y0, from(nil))) -> c3(MARK(first(y0, from(nil))))
   A__FROM(first(y0, from(s(y1)))) -> c3(MARK(first(y0, from(s(y1)))))
   A__FROM(first(y0, from(cons(y1, y2)))) -> c3(MARK(first(y0, from(cons(y1, y2)))))
   A__FROM(first(first(y0, y1), from(y2))) -> c3(MARK(first(first(y0, y1), from(y2))))
   A__FROM(first(from(y0), from(y1))) -> c3(MARK(first(from(y0), from(y1))))
   A__FROM(first(s(y0), from(y1))) -> c3(MARK(first(s(y0), from(y1))))
   A__FROM(first(cons(y0, y1), from(y2))) -> c3(MARK(first(cons(y0, y1), from(y2))))
   A__FROM(first(y0, cons(first(y1, y2), y3))) -> c3(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FROM(first(y0, cons(from(y1), y2))) -> c3(MARK(first(y0, cons(from(y1), y2))))
   A__FROM(first(y0, cons(s(y1), y2))) -> c3(MARK(first(y0, cons(s(y1), y2))))
   A__FROM(first(y0, cons(cons(y1, y2), y3))) -> c3(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), cons(y2, y3))) -> c3(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FROM(first(from(y0), cons(y1, y2))) -> c3(MARK(first(from(y0), cons(y1, y2))))
   A__FROM(first(s(y0), cons(y1, y2))) -> c3(MARK(first(s(y0), cons(y1, y2))))
   A__FROM(first(cons(y0, y1), cons(y2, y3))) -> c3(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FROM(first(first(y0, first(y1, y2)), y3)) -> c3(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FROM(first(first(y0, from(y1)), y2)) -> c3(MARK(first(first(y0, from(y1)), y2)))
   A__FROM(first(first(y0, 0), y1)) -> c3(MARK(first(first(y0, 0), y1)))
   A__FROM(first(first(y0, nil), y1)) -> c3(MARK(first(first(y0, nil), y1)))
   A__FROM(first(first(y0, s(y1)), y2)) -> c3(MARK(first(first(y0, s(y1)), y2)))
   A__FROM(first(first(y0, cons(y1, y2)), y3)) -> c3(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FROM(first(first(first(y0, y1), y2), y3)) -> c3(MARK(first(first(first(y0, y1), y2), y3)))
   A__FROM(first(first(from(y0), y1), y2)) -> c3(MARK(first(first(from(y0), y1), y2)))
   A__FROM(first(first(0, y0), y1)) -> c3(MARK(first(first(0, y0), y1)))
   A__FROM(first(first(nil, y0), y1)) -> c3(MARK(first(first(nil, y0), y1)))
   A__FROM(first(first(s(y0), y1), y2)) -> c3(MARK(first(first(s(y0), y1), y2)))
   A__FROM(first(first(cons(y0, y1), y2), y3)) -> c3(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FROM(first(first(y0, y1), 0)) -> c3(MARK(first(first(y0, y1), 0)))
   A__FROM(first(first(y0, y1), nil)) -> c3(MARK(first(first(y0, y1), nil)))
   A__FROM(first(first(y0, y1), s(y2))) -> c3(MARK(first(first(y0, y1), s(y2))))
   A__FROM(first(first(y0, y1), y2)) -> c3(MARK(first(first(y0, y1), y2)))
   A__FROM(first(from(first(y0, y1)), y2)) -> c3(MARK(first(from(first(y0, y1)), y2)))
   A__FROM(first(from(from(y0)), y1)) -> c3(MARK(first(from(from(y0)), y1)))
   A__FROM(first(from(0), y0)) -> c3(MARK(first(from(0), y0)))
   A__FROM(first(from(nil), y0)) -> c3(MARK(first(from(nil), y0)))
   A__FROM(first(from(s(y0)), y1)) -> c3(MARK(first(from(s(y0)), y1)))
   A__FROM(first(from(cons(y0, y1)), y2)) -> c3(MARK(first(from(cons(y0, y1)), y2)))
   A__FROM(first(from(y0), y1)) -> c3(MARK(first(from(y0), y1)))
   A__FROM(first(from(y0), 0)) -> c3(MARK(first(from(y0), 0)))
   A__FROM(first(from(y0), nil)) -> c3(MARK(first(from(y0), nil)))
   A__FROM(first(from(y0), s(y1))) -> c3(MARK(first(from(y0), s(y1))))
   A__FROM(first(s(first(y0, y1)), y2)) -> c3(MARK(first(s(first(y0, y1)), y2)))
   A__FROM(first(s(from(y0)), y1)) -> c3(MARK(first(s(from(y0)), y1)))
   A__FROM(first(s(0), y0)) -> c3(MARK(first(s(0), y0)))
   A__FROM(first(s(nil), y0)) -> c3(MARK(first(s(nil), y0)))
   A__FROM(first(s(s(y0)), y1)) -> c3(MARK(first(s(s(y0)), y1)))
   A__FROM(first(s(cons(y0, y1)), y2)) -> c3(MARK(first(s(cons(y0, y1)), y2)))
   A__FROM(first(s(y0), y1)) -> c3(MARK(first(s(y0), y1)))
   A__FROM(first(s(y0), 0)) -> c3(MARK(first(s(y0), 0)))
   A__FROM(first(s(y0), nil)) -> c3(MARK(first(s(y0), nil)))
   A__FROM(first(s(y0), s(y1))) -> c3(MARK(first(s(y0), s(y1))))
   A__FROM(first(0, first(y0, y1))) -> c3(MARK(first(0, first(y0, y1))))
   A__FROM(first(nil, first(y0, y1))) -> c3(MARK(first(nil, first(y0, y1))))
   A__FROM(first(0, from(y0))) -> c3(MARK(first(0, from(y0))))
   A__FROM(first(nil, from(y0))) -> c3(MARK(first(nil, from(y0))))
   A__FROM(first(y0, cons(y1, y2))) -> c3(MARK(first(y0, cons(y1, y2))))
   A__FROM(first(0, cons(y0, y1))) -> c3(MARK(first(0, cons(y0, y1))))
   A__FROM(first(nil, cons(y0, y1))) -> c3(MARK(first(nil, cons(y0, y1))))
   A__FROM(first(y0, cons(0, y1))) -> c3(MARK(first(y0, cons(0, y1))))
   A__FROM(first(y0, cons(nil, y1))) -> c3(MARK(first(y0, cons(nil, y1))))
   MARK(from(s(z0))) -> c7(A__FROM(s(mark(z0))), MARK(s(z0)))
   MARK(from(cons(z0, z1))) -> c7(A__FROM(cons(mark(z0), z1)), MARK(cons(z0, z1)))
   MARK(first(from(0), x1)) -> c5(A__FIRST(a__from(0), mark(x1)))
   MARK(first(from(nil), x1)) -> c5(A__FIRST(a__from(nil), mark(x1)))
   MARK(first(x0, from(0))) -> c6(A__FIRST(mark(x0), a__from(0)))
   MARK(first(x0, from(nil))) -> c6(A__FIRST(mark(x0), a__from(nil)))
   MARK(from(first(x0, x1))) -> c7(A__FROM(first(mark(x0), mark(x1))), MARK(first(x0, x1)))
   MARK(from(first(x0, first(z0, z1)))) -> c7(A__FROM(a__first(mark(x0), a__first(mark(z0), mark(z1)))), MARK(first(x0, first(z0, z1))))
   MARK(from(first(x0, from(z0)))) -> c7(A__FROM(a__first(mark(x0), a__from(mark(z0)))), MARK(first(x0, from(z0))))
   MARK(from(first(x0, 0))) -> c7(A__FROM(a__first(mark(x0), 0)), MARK(first(x0, 0)))
   MARK(from(first(x0, nil))) -> c7(A__FROM(a__first(mark(x0), nil)), MARK(first(x0, nil)))
   MARK(from(first(x0, s(z0)))) -> c7(A__FROM(a__first(mark(x0), s(mark(z0)))), MARK(first(x0, s(z0))))
   MARK(from(first(x0, cons(z0, z1)))) -> c7(A__FROM(a__first(mark(x0), cons(mark(z0), z1))), MARK(first(x0, cons(z0, z1))))
   MARK(from(first(first(z0, z1), x1))) -> c7(A__FROM(a__first(a__first(mark(z0), mark(z1)), mark(x1))), MARK(first(first(z0, z1), x1)))
   MARK(from(first(from(z0), x1))) -> c7(A__FROM(a__first(a__from(mark(z0)), mark(x1))), MARK(first(from(z0), x1)))
   MARK(from(first(0, x1))) -> c7(A__FROM(a__first(0, mark(x1))), MARK(first(0, x1)))
   MARK(from(first(nil, x1))) -> c7(A__FROM(a__first(nil, mark(x1))), MARK(first(nil, x1)))
   MARK(from(first(s(z0), x1))) -> c7(A__FROM(a__first(s(mark(z0)), mark(x1))), MARK(first(s(z0), x1)))
   MARK(from(first(cons(z0, z1), x1))) -> c7(A__FROM(a__first(cons(mark(z0), z1), mark(x1))), MARK(first(cons(z0, z1), x1)))
   MARK(from(from(x0))) -> c7(A__FROM(cons(mark(mark(x0)), from(s(mark(x0))))), MARK(from(x0)))
   MARK(from(from(x0))) -> c7(A__FROM(from(mark(x0))), MARK(from(x0)))
   MARK(from(from(first(z0, z1)))) -> c7(A__FROM(a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(from(from(from(z0)))) -> c7(A__FROM(a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(from(from(s(z0)))) -> c7(A__FROM(a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(from(from(cons(z0, z1)))) -> c7(A__FROM(a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(from(from(0))) -> c7(A__FROM(a__from(0)))
   MARK(from(from(nil))) -> c7(A__FROM(a__from(nil)))
   MARK(s(s(y0))) -> c10(MARK(s(y0)))
   MARK(s(cons(y0, y1))) -> c10(MARK(cons(y0, y1)))
   MARK(s(first(y0, 0))) -> c10(MARK(first(y0, 0)))
   MARK(s(first(y0, nil))) -> c10(MARK(first(y0, nil)))
   MARK(s(first(y0, s(y1)))) -> c10(MARK(first(y0, s(y1))))
   MARK(s(first(cons(y0, y1), y2))) -> c10(MARK(first(cons(y0, y1), y2)))
   MARK(s(first(0, y0))) -> c10(MARK(first(0, y0)))
   MARK(s(first(nil, y0))) -> c10(MARK(first(nil, y0)))
   MARK(s(first(y0, first(y1, first(y2, y3))))) -> c10(MARK(first(y0, first(y1, first(y2, y3)))))
   MARK(s(first(y0, first(y1, from(y2))))) -> c10(MARK(first(y0, first(y1, from(y2)))))
   MARK(s(first(y0, first(y1, 0)))) -> c10(MARK(first(y0, first(y1, 0))))
   MARK(s(first(y0, first(y1, nil)))) -> c10(MARK(first(y0, first(y1, nil))))
   MARK(s(first(y0, first(y1, s(y2))))) -> c10(MARK(first(y0, first(y1, s(y2)))))
   MARK(s(first(y0, first(y1, cons(y2, y3))))) -> c10(MARK(first(y0, first(y1, cons(y2, y3)))))
   MARK(s(first(y0, first(first(y1, y2), y3)))) -> c10(MARK(first(y0, first(first(y1, y2), y3))))
   MARK(s(first(y0, first(from(y1), y2)))) -> c10(MARK(first(y0, first(from(y1), y2))))
   MARK(s(first(y0, first(0, y1)))) -> c10(MARK(first(y0, first(0, y1))))
   MARK(s(first(y0, first(nil, y1)))) -> c10(MARK(first(y0, first(nil, y1))))
   MARK(s(first(y0, first(s(y1), y2)))) -> c10(MARK(first(y0, first(s(y1), y2))))
   MARK(s(first(y0, first(cons(y1, y2), y3)))) -> c10(MARK(first(y0, first(cons(y1, y2), y3))))
   MARK(s(first(first(y0, y1), first(y2, y3)))) -> c10(MARK(first(first(y0, y1), first(y2, y3))))
   MARK(s(first(from(y0), first(y1, y2)))) -> c10(MARK(first(from(y0), first(y1, y2))))
   MARK(s(first(s(y0), first(y1, y2)))) -> c10(MARK(first(s(y0), first(y1, y2))))
   MARK(s(first(y0, first(y1, y2)))) -> c10(MARK(first(y0, first(y1, y2))))
   MARK(s(first(cons(y0, y1), first(y2, y3)))) -> c10(MARK(first(cons(y0, y1), first(y2, y3))))
   MARK(s(first(y0, from(y1)))) -> c10(MARK(first(y0, from(y1))))
   MARK(s(first(y0, from(first(y1, y2))))) -> c10(MARK(first(y0, from(first(y1, y2)))))
   MARK(s(first(y0, from(from(y1))))) -> c10(MARK(first(y0, from(from(y1)))))
   MARK(s(first(y0, from(0)))) -> c10(MARK(first(y0, from(0))))
   MARK(s(first(y0, from(nil)))) -> c10(MARK(first(y0, from(nil))))
   MARK(s(first(y0, from(s(y1))))) -> c10(MARK(first(y0, from(s(y1)))))
   MARK(s(first(y0, from(cons(y1, y2))))) -> c10(MARK(first(y0, from(cons(y1, y2)))))
   MARK(s(first(first(y0, y1), from(y2)))) -> c10(MARK(first(first(y0, y1), from(y2))))
   MARK(s(first(from(y0), from(y1)))) -> c10(MARK(first(from(y0), from(y1))))
   MARK(s(first(s(y0), from(y1)))) -> c10(MARK(first(s(y0), from(y1))))
   MARK(s(first(cons(y0, y1), from(y2)))) -> c10(MARK(first(cons(y0, y1), from(y2))))
   MARK(s(first(y0, cons(first(y1, y2), y3)))) -> c10(MARK(first(y0, cons(first(y1, y2), y3))))
   MARK(s(first(y0, cons(from(y1), y2)))) -> c10(MARK(first(y0, cons(from(y1), y2))))
   MARK(s(first(y0, cons(s(y1), y2)))) -> c10(MARK(first(y0, cons(s(y1), y2))))
   MARK(s(first(y0, cons(cons(y1, y2), y3)))) -> c10(MARK(first(y0, cons(cons(y1, y2), y3))))
   MARK(s(first(first(y0, y1), cons(y2, y3)))) -> c10(MARK(first(first(y0, y1), cons(y2, y3))))
   MARK(s(first(from(y0), cons(y1, y2)))) -> c10(MARK(first(from(y0), cons(y1, y2))))
   MARK(s(first(s(y0), cons(y1, y2)))) -> c10(MARK(first(s(y0), cons(y1, y2))))
   MARK(s(first(cons(y0, y1), cons(y2, y3)))) -> c10(MARK(first(cons(y0, y1), cons(y2, y3))))
   MARK(s(first(first(y0, first(y1, y2)), y3))) -> c10(MARK(first(first(y0, first(y1, y2)), y3)))
   MARK(s(first(first(y0, from(y1)), y2))) -> c10(MARK(first(first(y0, from(y1)), y2)))
   MARK(s(first(first(y0, 0), y1))) -> c10(MARK(first(first(y0, 0), y1)))
   MARK(s(first(first(y0, nil), y1))) -> c10(MARK(first(first(y0, nil), y1)))
   MARK(s(first(first(y0, s(y1)), y2))) -> c10(MARK(first(first(y0, s(y1)), y2)))
   MARK(s(first(first(y0, cons(y1, y2)), y3))) -> c10(MARK(first(first(y0, cons(y1, y2)), y3)))
   MARK(s(first(first(first(y0, y1), y2), y3))) -> c10(MARK(first(first(first(y0, y1), y2), y3)))
   MARK(s(first(first(from(y0), y1), y2))) -> c10(MARK(first(first(from(y0), y1), y2)))
   MARK(s(first(first(0, y0), y1))) -> c10(MARK(first(first(0, y0), y1)))
   MARK(s(first(first(nil, y0), y1))) -> c10(MARK(first(first(nil, y0), y1)))
   MARK(s(first(first(s(y0), y1), y2))) -> c10(MARK(first(first(s(y0), y1), y2)))
   MARK(s(first(first(cons(y0, y1), y2), y3))) -> c10(MARK(first(first(cons(y0, y1), y2), y3)))
   MARK(s(first(first(y0, y1), 0))) -> c10(MARK(first(first(y0, y1), 0)))
   MARK(s(first(first(y0, y1), nil))) -> c10(MARK(first(first(y0, y1), nil)))
   MARK(s(first(first(y0, y1), s(y2)))) -> c10(MARK(first(first(y0, y1), s(y2))))
   MARK(s(first(first(y0, y1), y2))) -> c10(MARK(first(first(y0, y1), y2)))
   MARK(s(first(from(first(y0, y1)), y2))) -> c10(MARK(first(from(first(y0, y1)), y2)))
   MARK(s(first(from(from(y0)), y1))) -> c10(MARK(first(from(from(y0)), y1)))
   MARK(s(first(from(s(y0)), y1))) -> c10(MARK(first(from(s(y0)), y1)))
   MARK(s(first(from(cons(y0, y1)), y2))) -> c10(MARK(first(from(cons(y0, y1)), y2)))
   MARK(s(first(from(y0), y1))) -> c10(MARK(first(from(y0), y1)))
   MARK(s(first(from(y0), 0))) -> c10(MARK(first(from(y0), 0)))
   MARK(s(first(from(y0), nil))) -> c10(MARK(first(from(y0), nil)))
   MARK(s(first(from(y0), s(y1)))) -> c10(MARK(first(from(y0), s(y1))))
   MARK(s(first(s(first(y0, y1)), y2))) -> c10(MARK(first(s(first(y0, y1)), y2)))
   MARK(s(first(s(from(y0)), y1))) -> c10(MARK(first(s(from(y0)), y1)))
   MARK(s(first(s(0), y0))) -> c10(MARK(first(s(0), y0)))
   MARK(s(first(s(nil), y0))) -> c10(MARK(first(s(nil), y0)))
   MARK(s(first(s(s(y0)), y1))) -> c10(MARK(first(s(s(y0)), y1)))
   MARK(s(first(s(cons(y0, y1)), y2))) -> c10(MARK(first(s(cons(y0, y1)), y2)))
   MARK(s(first(s(y0), y1))) -> c10(MARK(first(s(y0), y1)))
   MARK(s(first(s(y0), 0))) -> c10(MARK(first(s(y0), 0)))
   MARK(s(first(s(y0), nil))) -> c10(MARK(first(s(y0), nil)))
   MARK(s(first(s(y0), s(y1)))) -> c10(MARK(first(s(y0), s(y1))))
   MARK(s(first(0, first(y0, y1)))) -> c10(MARK(first(0, first(y0, y1))))
   MARK(s(first(nil, first(y0, y1)))) -> c10(MARK(first(nil, first(y0, y1))))
   MARK(s(first(0, from(y0)))) -> c10(MARK(first(0, from(y0))))
   MARK(s(first(nil, from(y0)))) -> c10(MARK(first(nil, from(y0))))
   MARK(s(first(y0, cons(y1, y2)))) -> c10(MARK(first(y0, cons(y1, y2))))
   MARK(s(first(0, cons(y0, y1)))) -> c10(MARK(first(0, cons(y0, y1))))
   MARK(s(first(nil, cons(y0, y1)))) -> c10(MARK(first(nil, cons(y0, y1))))
   MARK(s(first(from(0), y0))) -> c10(MARK(first(from(0), y0)))
   MARK(s(first(from(nil), y0))) -> c10(MARK(first(from(nil), y0)))
   MARK(s(first(y0, cons(0, y1)))) -> c10(MARK(first(y0, cons(0, y1))))
   MARK(s(first(y0, cons(nil, y1)))) -> c10(MARK(first(y0, cons(nil, y1))))
   MARK(s(from(s(y0)))) -> c10(MARK(from(s(y0))))
   MARK(s(from(cons(y0, y1)))) -> c10(MARK(from(cons(y0, y1))))
   MARK(s(from(first(y0, y1)))) -> c10(MARK(from(first(y0, y1))))
   MARK(s(from(first(y0, first(y1, y2))))) -> c10(MARK(from(first(y0, first(y1, y2)))))
   MARK(s(from(first(y0, from(y1))))) -> c10(MARK(from(first(y0, from(y1)))))
   MARK(s(from(first(y0, 0)))) -> c10(MARK(from(first(y0, 0))))
   MARK(s(from(first(y0, nil)))) -> c10(MARK(from(first(y0, nil))))
   MARK(s(from(first(y0, s(y1))))) -> c10(MARK(from(first(y0, s(y1)))))
   MARK(s(from(first(y0, cons(y1, y2))))) -> c10(MARK(from(first(y0, cons(y1, y2)))))
   MARK(s(from(first(first(y0, y1), y2)))) -> c10(MARK(from(first(first(y0, y1), y2))))
   MARK(s(from(first(from(y0), y1)))) -> c10(MARK(from(first(from(y0), y1))))
   MARK(s(from(first(0, y0)))) -> c10(MARK(from(first(0, y0))))
   MARK(s(from(first(nil, y0)))) -> c10(MARK(from(first(nil, y0))))
   MARK(s(from(first(s(y0), y1)))) -> c10(MARK(from(first(s(y0), y1))))
   MARK(s(from(first(cons(y0, y1), y2)))) -> c10(MARK(from(first(cons(y0, y1), y2))))
   MARK(s(from(from(y0)))) -> c10(MARK(from(from(y0))))
   MARK(s(from(from(first(y0, y1))))) -> c10(MARK(from(from(first(y0, y1)))))
   MARK(s(from(from(from(y0))))) -> c10(MARK(from(from(from(y0)))))
   MARK(s(from(from(s(y0))))) -> c10(MARK(from(from(s(y0)))))
   MARK(s(from(from(cons(y0, y1))))) -> c10(MARK(from(from(cons(y0, y1)))))
   MARK(s(from(from(0)))) -> c10(MARK(from(from(0))))
   MARK(s(from(from(nil)))) -> c10(MARK(from(from(nil))))
   MARK(first(s(0), x1)) -> c5(A__FIRST(s(0), mark(x1)))
   MARK(first(s(nil), x1)) -> c5(A__FIRST(s(nil), mark(x1)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   MARK_1, A__FIRST_2, A__FROM_1

Compound Symbols:   c11_1, c5_1, c6_1, c5_2, c6_2, c1_1, c3_1, c7_2, c7_1, c10_1


----------------------------------------

(119) CdtForwardInstantiationProof (BOTH BOUNDS(ID, ID))
Use forward instantiation to replace MARK(cons(z0, z1)) -> c11(MARK(z0)) by 
   MARK(cons(cons(y0, y1), z1)) -> c11(MARK(cons(y0, y1)))
   MARK(cons(first(y0, 0), z1)) -> c11(MARK(first(y0, 0)))
   MARK(cons(first(y0, nil), z1)) -> c11(MARK(first(y0, nil)))
   MARK(cons(first(y0, s(y1)), z1)) -> c11(MARK(first(y0, s(y1))))
   MARK(cons(first(cons(y0, y1), y2), z1)) -> c11(MARK(first(cons(y0, y1), y2)))
   MARK(cons(first(0, y0), z1)) -> c11(MARK(first(0, y0)))
   MARK(cons(first(nil, y0), z1)) -> c11(MARK(first(nil, y0)))
   MARK(cons(first(y0, first(y1, first(y2, y3))), z1)) -> c11(MARK(first(y0, first(y1, first(y2, y3)))))
   MARK(cons(first(y0, first(y1, from(y2))), z1)) -> c11(MARK(first(y0, first(y1, from(y2)))))
   MARK(cons(first(y0, first(y1, 0)), z1)) -> c11(MARK(first(y0, first(y1, 0))))
   MARK(cons(first(y0, first(y1, nil)), z1)) -> c11(MARK(first(y0, first(y1, nil))))
   MARK(cons(first(y0, first(y1, s(y2))), z1)) -> c11(MARK(first(y0, first(y1, s(y2)))))
   MARK(cons(first(y0, first(y1, cons(y2, y3))), z1)) -> c11(MARK(first(y0, first(y1, cons(y2, y3)))))
   MARK(cons(first(y0, first(first(y1, y2), y3)), z1)) -> c11(MARK(first(y0, first(first(y1, y2), y3))))
   MARK(cons(first(y0, first(from(y1), y2)), z1)) -> c11(MARK(first(y0, first(from(y1), y2))))
   MARK(cons(first(y0, first(0, y1)), z1)) -> c11(MARK(first(y0, first(0, y1))))
   MARK(cons(first(y0, first(nil, y1)), z1)) -> c11(MARK(first(y0, first(nil, y1))))
   MARK(cons(first(y0, first(s(y1), y2)), z1)) -> c11(MARK(first(y0, first(s(y1), y2))))
   MARK(cons(first(y0, first(cons(y1, y2), y3)), z1)) -> c11(MARK(first(y0, first(cons(y1, y2), y3))))
   MARK(cons(first(first(y0, y1), first(y2, y3)), z1)) -> c11(MARK(first(first(y0, y1), first(y2, y3))))
   MARK(cons(first(from(y0), first(y1, y2)), z1)) -> c11(MARK(first(from(y0), first(y1, y2))))
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   MARK(cons(s(from(first(y0, first(y1, y2)))), z1)) -> c11(MARK(s(from(first(y0, first(y1, y2))))))
   MARK(cons(s(from(first(y0, from(y1)))), z1)) -> c11(MARK(s(from(first(y0, from(y1))))))
   MARK(cons(s(from(first(y0, 0))), z1)) -> c11(MARK(s(from(first(y0, 0)))))
   MARK(cons(s(from(first(y0, nil))), z1)) -> c11(MARK(s(from(first(y0, nil)))))
   MARK(cons(s(from(first(y0, s(y1)))), z1)) -> c11(MARK(s(from(first(y0, s(y1))))))
   MARK(cons(s(from(first(y0, cons(y1, y2)))), z1)) -> c11(MARK(s(from(first(y0, cons(y1, y2))))))
   MARK(cons(s(from(first(first(y0, y1), y2))), z1)) -> c11(MARK(s(from(first(first(y0, y1), y2)))))
   MARK(cons(s(from(first(from(y0), y1))), z1)) -> c11(MARK(s(from(first(from(y0), y1)))))
   MARK(cons(s(from(first(0, y0))), z1)) -> c11(MARK(s(from(first(0, y0)))))
   MARK(cons(s(from(first(nil, y0))), z1)) -> c11(MARK(s(from(first(nil, y0)))))
   MARK(cons(s(from(first(s(y0), y1))), z1)) -> c11(MARK(s(from(first(s(y0), y1)))))
   MARK(cons(s(from(first(cons(y0, y1), y2))), z1)) -> c11(MARK(s(from(first(cons(y0, y1), y2)))))
   MARK(cons(s(from(from(y0))), z1)) -> c11(MARK(s(from(from(y0)))))
   MARK(cons(s(from(from(first(y0, y1)))), z1)) -> c11(MARK(s(from(from(first(y0, y1))))))
   MARK(cons(s(from(from(from(y0)))), z1)) -> c11(MARK(s(from(from(from(y0))))))
   MARK(cons(s(from(from(s(y0)))), z1)) -> c11(MARK(s(from(from(s(y0))))))
   MARK(cons(s(from(from(cons(y0, y1)))), z1)) -> c11(MARK(s(from(from(cons(y0, y1))))))
   MARK(cons(s(from(from(0))), z1)) -> c11(MARK(s(from(from(0)))))
   MARK(cons(s(from(from(nil))), z1)) -> c11(MARK(s(from(from(nil)))))

----------------------------------------

(120)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, x1), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(first(x0, x1), x2)) -> c6(MARK(x2))
   MARK(first(from(first(z0, z1)), x1)) -> c6(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(from(from(z0)), x1)) -> c6(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(0), x1)) -> c6(A__FIRST(a__from(0), mark(x1)), MARK(x1))
   MARK(first(from(nil), x1)) -> c6(A__FIRST(a__from(nil), mark(x1)), MARK(x1))
   MARK(first(from(s(z0)), x1)) -> c6(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(cons(z0, z1)), x1)) -> c6(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(x1))
   MARK(first(from(x0), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(from(x0), x1)) -> c6(MARK(x1))
   MARK(first(s(first(z0, z1)), x1)) -> c6(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(s(from(z0)), x1)) -> c6(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(0), x1)) -> c6(A__FIRST(s(0), mark(x1)), MARK(x1))
   MARK(first(s(nil), x1)) -> c6(A__FIRST(s(nil), mark(x1)), MARK(x1))
   MARK(first(s(s(z0)), x1)) -> c6(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(cons(z0, z1)), x1)) -> c6(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(x1))
   MARK(first(s(x0), s(z0))) -> c6(MARK(s(z0)))
   A__FIRST(s(z0), cons(from(y0), z2)) -> c1(MARK(from(y0)))
   A__FIRST(s(z0), cons(s(y0), z2)) -> c1(MARK(s(y0)))
   A__FIRST(s(z0), cons(cons(y0, y1), z2)) -> c1(MARK(cons(y0, y1)))
   A__FIRST(s(z0), cons(first(y0, 0), z2)) -> c1(MARK(first(y0, 0)))
   A__FIRST(s(z0), cons(first(y0, nil), z2)) -> c1(MARK(first(y0, nil)))
   A__FIRST(s(z0), cons(first(y0, s(y1)), z2)) -> c1(MARK(first(y0, s(y1))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), y2), z2)) -> c1(MARK(first(cons(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(0, y0), z2)) -> c1(MARK(first(0, y0)))
   A__FIRST(s(z0), cons(first(nil, y0), z2)) -> c1(MARK(first(nil, y0)))
   A__FIRST(s(z0), cons(first(y0, first(y1, first(y2, y3))), z2)) -> c1(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FIRST(s(z0), cons(first(y0, first(y1, from(y2))), z2)) -> c1(MARK(first(y0, first(y1, from(y2)))))
   A__FIRST(s(z0), cons(first(y0, first(y1, 0)), z2)) -> c1(MARK(first(y0, first(y1, 0))))
   A__FIRST(s(z0), cons(first(y0, first(y1, nil)), z2)) -> c1(MARK(first(y0, first(y1, nil))))
   A__FIRST(s(z0), cons(first(y0, first(y1, s(y2))), z2)) -> c1(MARK(first(y0, first(y1, s(y2)))))
   A__FIRST(s(z0), cons(first(y0, first(y1, cons(y2, y3))), z2)) -> c1(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FIRST(s(z0), cons(first(y0, first(first(y1, y2), y3)), z2)) -> c1(MARK(first(y0, first(first(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(y0, first(from(y1), y2)), z2)) -> c1(MARK(first(y0, first(from(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, first(0, y1)), z2)) -> c1(MARK(first(y0, first(0, y1))))
   A__FIRST(s(z0), cons(first(y0, first(nil, y1)), z2)) -> c1(MARK(first(y0, first(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, first(s(y1), y2)), z2)) -> c1(MARK(first(y0, first(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, first(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), first(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), first(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), first(y1, y2)), z2)) -> c1(MARK(first(from(y0), first(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), first(y1, y2)), z2)) -> c1(MARK(first(s(y0), first(y1, y2))))
   A__FIRST(s(z0), cons(first(y0, first(y1, y2)), z2)) -> c1(MARK(first(y0, first(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), first(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FIRST(s(z0), cons(first(y0, from(y1)), z2)) -> c1(MARK(first(y0, from(y1))))
   A__FIRST(s(z0), cons(first(y0, from(first(y1, y2))), z2)) -> c1(MARK(first(y0, from(first(y1, y2)))))
   A__FIRST(s(z0), cons(first(y0, from(from(y1))), z2)) -> c1(MARK(first(y0, from(from(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(0)), z2)) -> c1(MARK(first(y0, from(0))))
   A__FIRST(s(z0), cons(first(y0, from(nil)), z2)) -> c1(MARK(first(y0, from(nil))))
   A__FIRST(s(z0), cons(first(y0, from(s(y1))), z2)) -> c1(MARK(first(y0, from(s(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(cons(y1, y2))), z2)) -> c1(MARK(first(y0, from(cons(y1, y2)))))
   A__FIRST(s(z0), cons(first(first(y0, y1), from(y2)), z2)) -> c1(MARK(first(first(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(from(y0), from(y1)), z2)) -> c1(MARK(first(from(y0), from(y1))))
   A__FIRST(s(z0), cons(first(s(y0), from(y1)), z2)) -> c1(MARK(first(s(y0), from(y1))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), from(y2)), z2)) -> c1(MARK(first(cons(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(y0, cons(first(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(y0, cons(from(y1), y2)), z2)) -> c1(MARK(first(y0, cons(from(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(0, y1)), z2)) -> c1(MARK(first(y0, cons(0, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(nil, y1)), z2)) -> c1(MARK(first(y0, cons(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(s(y1), y2)), z2)) -> c1(MARK(first(y0, cons(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), cons(y1, y2)), z2)) -> c1(MARK(first(from(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), cons(y1, y2)), z2)) -> c1(MARK(first(s(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(first(y0, first(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(y0, from(y1)), y2), z2)) -> c1(MARK(first(first(y0, from(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, 0), y1), z2)) -> c1(MARK(first(first(y0, 0), y1)))
   A__FIRST(s(z0), cons(first(first(y0, nil), y1), z2)) -> c1(MARK(first(first(y0, nil), y1)))
   A__FIRST(s(z0), cons(first(first(y0, s(y1)), y2), z2)) -> c1(MARK(first(first(y0, s(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, cons(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(first(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(first(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(from(y0), y1), y2), z2)) -> c1(MARK(first(first(from(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(0, y0), y1), z2)) -> c1(MARK(first(first(0, y0), y1)))
   A__FIRST(s(z0), cons(first(first(nil, y0), y1), z2)) -> c1(MARK(first(first(nil, y0), y1)))
   A__FIRST(s(z0), cons(first(first(s(y0), y1), y2), z2)) -> c1(MARK(first(first(s(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(cons(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(y0, y1), 0), z2)) -> c1(MARK(first(first(y0, y1), 0)))
   A__FIRST(s(z0), cons(first(first(y0, y1), nil), z2)) -> c1(MARK(first(first(y0, y1), nil)))
   A__FIRST(s(z0), cons(first(first(y0, y1), s(y2)), z2)) -> c1(MARK(first(first(y0, y1), s(y2))))
   A__FIRST(s(z0), cons(first(first(y0, y1), y2), z2)) -> c1(MARK(first(first(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(from(first(y0, y1)), y2), z2)) -> c1(MARK(first(from(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(from(y0)), y1), z2)) -> c1(MARK(first(from(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(0), y0), z2)) -> c1(MARK(first(from(0), y0)))
   A__FIRST(s(z0), cons(first(from(nil), y0), z2)) -> c1(MARK(first(from(nil), y0)))
   A__FIRST(s(z0), cons(first(from(s(y0)), y1), z2)) -> c1(MARK(first(from(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(cons(y0, y1)), y2), z2)) -> c1(MARK(first(from(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(y0), y1), z2)) -> c1(MARK(first(from(y0), y1)))
   A__FIRST(s(z0), cons(first(from(y0), 0), z2)) -> c1(MARK(first(from(y0), 0)))
   A__FIRST(s(z0), cons(first(from(y0), nil), z2)) -> c1(MARK(first(from(y0), nil)))
   A__FIRST(s(z0), cons(first(from(y0), s(y1)), z2)) -> c1(MARK(first(from(y0), s(y1))))
   A__FIRST(s(z0), cons(first(s(first(y0, y1)), y2), z2)) -> c1(MARK(first(s(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(from(y0)), y1), z2)) -> c1(MARK(first(s(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(0), y0), z2)) -> c1(MARK(first(s(0), y0)))
   A__FIRST(s(z0), cons(first(s(nil), y0), z2)) -> c1(MARK(first(s(nil), y0)))
   A__FIRST(s(z0), cons(first(s(s(y0)), y1), z2)) -> c1(MARK(first(s(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(cons(y0, y1)), y2), z2)) -> c1(MARK(first(s(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(y0), y1), z2)) -> c1(MARK(first(s(y0), y1)))
   A__FIRST(s(z0), cons(first(s(y0), 0), z2)) -> c1(MARK(first(s(y0), 0)))
   A__FIRST(s(z0), cons(first(s(y0), nil), z2)) -> c1(MARK(first(s(y0), nil)))
   A__FIRST(s(z0), cons(first(s(y0), s(y1)), z2)) -> c1(MARK(first(s(y0), s(y1))))
   A__FIRST(s(z0), cons(first(0, first(y0, y1)), z2)) -> c1(MARK(first(0, first(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, first(y0, y1)), z2)) -> c1(MARK(first(nil, first(y0, y1))))
   A__FIRST(s(z0), cons(first(0, from(y0)), z2)) -> c1(MARK(first(0, from(y0))))
   A__FIRST(s(z0), cons(first(nil, from(y0)), z2)) -> c1(MARK(first(nil, from(y0))))
   A__FIRST(s(z0), cons(first(y0, cons(y1, y2)), z2)) -> c1(MARK(first(y0, cons(y1, y2))))
   A__FIRST(s(z0), cons(first(0, cons(y0, y1)), z2)) -> c1(MARK(first(0, cons(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, cons(y0, y1)), z2)) -> c1(MARK(first(nil, cons(y0, y1))))
   MARK(first(x0, cons(0, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(0, x2))) -> c6(MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(MARK(cons(nil, x2)))
   A__FROM(from(y0)) -> c3(MARK(from(y0)))
   A__FROM(s(y0)) -> c3(MARK(s(y0)))
   A__FROM(cons(y0, y1)) -> c3(MARK(cons(y0, y1)))
   A__FROM(first(y0, 0)) -> c3(MARK(first(y0, 0)))
   A__FROM(first(y0, nil)) -> c3(MARK(first(y0, nil)))
   A__FROM(first(y0, s(y1))) -> c3(MARK(first(y0, s(y1))))
   A__FROM(first(cons(y0, y1), y2)) -> c3(MARK(first(cons(y0, y1), y2)))
   A__FROM(first(0, y0)) -> c3(MARK(first(0, y0)))
   A__FROM(first(nil, y0)) -> c3(MARK(first(nil, y0)))
   A__FROM(first(y0, first(y1, first(y2, y3)))) -> c3(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FROM(first(y0, first(y1, from(y2)))) -> c3(MARK(first(y0, first(y1, from(y2)))))
   A__FROM(first(y0, first(y1, 0))) -> c3(MARK(first(y0, first(y1, 0))))
   A__FROM(first(y0, first(y1, nil))) -> c3(MARK(first(y0, first(y1, nil))))
   A__FROM(first(y0, first(y1, s(y2)))) -> c3(MARK(first(y0, first(y1, s(y2)))))
   A__FROM(first(y0, first(y1, cons(y2, y3)))) -> c3(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FROM(first(y0, first(first(y1, y2), y3))) -> c3(MARK(first(y0, first(first(y1, y2), y3))))
   A__FROM(first(y0, first(from(y1), y2))) -> c3(MARK(first(y0, first(from(y1), y2))))
   A__FROM(first(y0, first(0, y1))) -> c3(MARK(first(y0, first(0, y1))))
   A__FROM(first(y0, first(nil, y1))) -> c3(MARK(first(y0, first(nil, y1))))
   A__FROM(first(y0, first(s(y1), y2))) -> c3(MARK(first(y0, first(s(y1), y2))))
   A__FROM(first(y0, first(cons(y1, y2), y3))) -> c3(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), first(y2, y3))) -> c3(MARK(first(first(y0, y1), first(y2, y3))))
   A__FROM(first(from(y0), first(y1, y2))) -> c3(MARK(first(from(y0), first(y1, y2))))
   A__FROM(first(s(y0), first(y1, y2))) -> c3(MARK(first(s(y0), first(y1, y2))))
   A__FROM(first(y0, first(y1, y2))) -> c3(MARK(first(y0, first(y1, y2))))
   A__FROM(first(cons(y0, y1), first(y2, y3))) -> c3(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FROM(first(y0, from(y1))) -> c3(MARK(first(y0, from(y1))))
   A__FROM(first(y0, from(first(y1, y2)))) -> c3(MARK(first(y0, from(first(y1, y2)))))
   A__FROM(first(y0, from(from(y1)))) -> c3(MARK(first(y0, from(from(y1)))))
   A__FROM(first(y0, from(0))) -> c3(MARK(first(y0, from(0))))
   A__FROM(first(y0, from(nil))) -> c3(MARK(first(y0, from(nil))))
   A__FROM(first(y0, from(s(y1)))) -> c3(MARK(first(y0, from(s(y1)))))
   A__FROM(first(y0, from(cons(y1, y2)))) -> c3(MARK(first(y0, from(cons(y1, y2)))))
   A__FROM(first(first(y0, y1), from(y2))) -> c3(MARK(first(first(y0, y1), from(y2))))
   A__FROM(first(from(y0), from(y1))) -> c3(MARK(first(from(y0), from(y1))))
   A__FROM(first(s(y0), from(y1))) -> c3(MARK(first(s(y0), from(y1))))
   A__FROM(first(cons(y0, y1), from(y2))) -> c3(MARK(first(cons(y0, y1), from(y2))))
   A__FROM(first(y0, cons(first(y1, y2), y3))) -> c3(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FROM(first(y0, cons(from(y1), y2))) -> c3(MARK(first(y0, cons(from(y1), y2))))
   A__FROM(first(y0, cons(s(y1), y2))) -> c3(MARK(first(y0, cons(s(y1), y2))))
   A__FROM(first(y0, cons(cons(y1, y2), y3))) -> c3(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), cons(y2, y3))) -> c3(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FROM(first(from(y0), cons(y1, y2))) -> c3(MARK(first(from(y0), cons(y1, y2))))
   A__FROM(first(s(y0), cons(y1, y2))) -> c3(MARK(first(s(y0), cons(y1, y2))))
   A__FROM(first(cons(y0, y1), cons(y2, y3))) -> c3(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FROM(first(first(y0, first(y1, y2)), y3)) -> c3(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FROM(first(first(y0, from(y1)), y2)) -> c3(MARK(first(first(y0, from(y1)), y2)))
   A__FROM(first(first(y0, 0), y1)) -> c3(MARK(first(first(y0, 0), y1)))
   A__FROM(first(first(y0, nil), y1)) -> c3(MARK(first(first(y0, nil), y1)))
   A__FROM(first(first(y0, s(y1)), y2)) -> c3(MARK(first(first(y0, s(y1)), y2)))
   A__FROM(first(first(y0, cons(y1, y2)), y3)) -> c3(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FROM(first(first(first(y0, y1), y2), y3)) -> c3(MARK(first(first(first(y0, y1), y2), y3)))
   A__FROM(first(first(from(y0), y1), y2)) -> c3(MARK(first(first(from(y0), y1), y2)))
   A__FROM(first(first(0, y0), y1)) -> c3(MARK(first(first(0, y0), y1)))
   A__FROM(first(first(nil, y0), y1)) -> c3(MARK(first(first(nil, y0), y1)))
   A__FROM(first(first(s(y0), y1), y2)) -> c3(MARK(first(first(s(y0), y1), y2)))
   A__FROM(first(first(cons(y0, y1), y2), y3)) -> c3(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FROM(first(first(y0, y1), 0)) -> c3(MARK(first(first(y0, y1), 0)))
   A__FROM(first(first(y0, y1), nil)) -> c3(MARK(first(first(y0, y1), nil)))
   A__FROM(first(first(y0, y1), s(y2))) -> c3(MARK(first(first(y0, y1), s(y2))))
   A__FROM(first(first(y0, y1), y2)) -> c3(MARK(first(first(y0, y1), y2)))
   A__FROM(first(from(first(y0, y1)), y2)) -> c3(MARK(first(from(first(y0, y1)), y2)))
   A__FROM(first(from(from(y0)), y1)) -> c3(MARK(first(from(from(y0)), y1)))
   A__FROM(first(from(0), y0)) -> c3(MARK(first(from(0), y0)))
   A__FROM(first(from(nil), y0)) -> c3(MARK(first(from(nil), y0)))
   A__FROM(first(from(s(y0)), y1)) -> c3(MARK(first(from(s(y0)), y1)))
   A__FROM(first(from(cons(y0, y1)), y2)) -> c3(MARK(first(from(cons(y0, y1)), y2)))
   A__FROM(first(from(y0), y1)) -> c3(MARK(first(from(y0), y1)))
   A__FROM(first(from(y0), 0)) -> c3(MARK(first(from(y0), 0)))
   A__FROM(first(from(y0), nil)) -> c3(MARK(first(from(y0), nil)))
   A__FROM(first(from(y0), s(y1))) -> c3(MARK(first(from(y0), s(y1))))
   A__FROM(first(s(first(y0, y1)), y2)) -> c3(MARK(first(s(first(y0, y1)), y2)))
   A__FROM(first(s(from(y0)), y1)) -> c3(MARK(first(s(from(y0)), y1)))
   A__FROM(first(s(0), y0)) -> c3(MARK(first(s(0), y0)))
   A__FROM(first(s(nil), y0)) -> c3(MARK(first(s(nil), y0)))
   A__FROM(first(s(s(y0)), y1)) -> c3(MARK(first(s(s(y0)), y1)))
   A__FROM(first(s(cons(y0, y1)), y2)) -> c3(MARK(first(s(cons(y0, y1)), y2)))
   A__FROM(first(s(y0), y1)) -> c3(MARK(first(s(y0), y1)))
   A__FROM(first(s(y0), 0)) -> c3(MARK(first(s(y0), 0)))
   A__FROM(first(s(y0), nil)) -> c3(MARK(first(s(y0), nil)))
   A__FROM(first(s(y0), s(y1))) -> c3(MARK(first(s(y0), s(y1))))
   A__FROM(first(0, first(y0, y1))) -> c3(MARK(first(0, first(y0, y1))))
   A__FROM(first(nil, first(y0, y1))) -> c3(MARK(first(nil, first(y0, y1))))
   A__FROM(first(0, from(y0))) -> c3(MARK(first(0, from(y0))))
   A__FROM(first(nil, from(y0))) -> c3(MARK(first(nil, from(y0))))
   A__FROM(first(y0, cons(y1, y2))) -> c3(MARK(first(y0, cons(y1, y2))))
   A__FROM(first(0, cons(y0, y1))) -> c3(MARK(first(0, cons(y0, y1))))
   A__FROM(first(nil, cons(y0, y1))) -> c3(MARK(first(nil, cons(y0, y1))))
   A__FROM(first(y0, cons(0, y1))) -> c3(MARK(first(y0, cons(0, y1))))
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   MARK(cons(first(from(first(y0, y1)), y2), z1)) -> c11(MARK(first(from(first(y0, y1)), y2)))
   MARK(cons(first(from(from(y0)), y1), z1)) -> c11(MARK(first(from(from(y0)), y1)))
   MARK(cons(first(from(s(y0)), y1), z1)) -> c11(MARK(first(from(s(y0)), y1)))
   MARK(cons(first(from(cons(y0, y1)), y2), z1)) -> c11(MARK(first(from(cons(y0, y1)), y2)))
   MARK(cons(first(from(y0), y1), z1)) -> c11(MARK(first(from(y0), y1)))
   MARK(cons(first(from(y0), 0), z1)) -> c11(MARK(first(from(y0), 0)))
   MARK(cons(first(from(y0), nil), z1)) -> c11(MARK(first(from(y0), nil)))
   MARK(cons(first(from(y0), s(y1)), z1)) -> c11(MARK(first(from(y0), s(y1))))
   MARK(cons(first(s(first(y0, y1)), y2), z1)) -> c11(MARK(first(s(first(y0, y1)), y2)))
   MARK(cons(first(s(from(y0)), y1), z1)) -> c11(MARK(first(s(from(y0)), y1)))
   MARK(cons(first(s(s(y0)), y1), z1)) -> c11(MARK(first(s(s(y0)), y1)))
   MARK(cons(first(s(cons(y0, y1)), y2), z1)) -> c11(MARK(first(s(cons(y0, y1)), y2)))
   MARK(cons(first(s(y0), y1), z1)) -> c11(MARK(first(s(y0), y1)))
   MARK(cons(first(s(y0), 0), z1)) -> c11(MARK(first(s(y0), 0)))
   MARK(cons(first(s(y0), nil), z1)) -> c11(MARK(first(s(y0), nil)))
   MARK(cons(first(s(y0), s(y1)), z1)) -> c11(MARK(first(s(y0), s(y1))))
   MARK(cons(first(0, first(y0, y1)), z1)) -> c11(MARK(first(0, first(y0, y1))))
   MARK(cons(first(nil, first(y0, y1)), z1)) -> c11(MARK(first(nil, first(y0, y1))))
   MARK(cons(first(0, from(y0)), z1)) -> c11(MARK(first(0, from(y0))))
   MARK(cons(first(nil, from(y0)), z1)) -> c11(MARK(first(nil, from(y0))))
   MARK(cons(first(y0, cons(y1, y2)), z1)) -> c11(MARK(first(y0, cons(y1, y2))))
   MARK(cons(first(0, cons(y0, y1)), z1)) -> c11(MARK(first(0, cons(y0, y1))))
   MARK(cons(first(nil, cons(y0, y1)), z1)) -> c11(MARK(first(nil, cons(y0, y1))))
   MARK(cons(first(from(0), y0), z1)) -> c11(MARK(first(from(0), y0)))
   MARK(cons(first(from(nil), y0), z1)) -> c11(MARK(first(from(nil), y0)))
   MARK(cons(first(s(0), y0), z1)) -> c11(MARK(first(s(0), y0)))
   MARK(cons(first(s(nil), y0), z1)) -> c11(MARK(first(s(nil), y0)))
   MARK(cons(first(y0, cons(0, y1)), z1)) -> c11(MARK(first(y0, cons(0, y1))))
   MARK(cons(first(y0, cons(nil, y1)), z1)) -> c11(MARK(first(y0, cons(nil, y1))))
   MARK(cons(from(s(y0)), z1)) -> c11(MARK(from(s(y0))))
   MARK(cons(from(cons(y0, y1)), z1)) -> c11(MARK(from(cons(y0, y1))))
   MARK(cons(from(first(y0, y1)), z1)) -> c11(MARK(from(first(y0, y1))))
   MARK(cons(from(first(y0, first(y1, y2))), z1)) -> c11(MARK(from(first(y0, first(y1, y2)))))
   MARK(cons(from(first(y0, from(y1))), z1)) -> c11(MARK(from(first(y0, from(y1)))))
   MARK(cons(from(first(y0, 0)), z1)) -> c11(MARK(from(first(y0, 0))))
   MARK(cons(from(first(y0, nil)), z1)) -> c11(MARK(from(first(y0, nil))))
   MARK(cons(from(first(y0, s(y1))), z1)) -> c11(MARK(from(first(y0, s(y1)))))
   MARK(cons(from(first(y0, cons(y1, y2))), z1)) -> c11(MARK(from(first(y0, cons(y1, y2)))))
   MARK(cons(from(first(first(y0, y1), y2)), z1)) -> c11(MARK(from(first(first(y0, y1), y2))))
   MARK(cons(from(first(from(y0), y1)), z1)) -> c11(MARK(from(first(from(y0), y1))))
   MARK(cons(from(first(0, y0)), z1)) -> c11(MARK(from(first(0, y0))))
   MARK(cons(from(first(nil, y0)), z1)) -> c11(MARK(from(first(nil, y0))))
   MARK(cons(from(first(s(y0), y1)), z1)) -> c11(MARK(from(first(s(y0), y1))))
   MARK(cons(from(first(cons(y0, y1), y2)), z1)) -> c11(MARK(from(first(cons(y0, y1), y2))))
   MARK(cons(from(from(y0)), z1)) -> c11(MARK(from(from(y0))))
   MARK(cons(from(from(first(y0, y1))), z1)) -> c11(MARK(from(from(first(y0, y1)))))
   MARK(cons(from(from(from(y0))), z1)) -> c11(MARK(from(from(from(y0)))))
   MARK(cons(from(from(s(y0))), z1)) -> c11(MARK(from(from(s(y0)))))
   MARK(cons(from(from(cons(y0, y1))), z1)) -> c11(MARK(from(from(cons(y0, y1)))))
   MARK(cons(from(from(0)), z1)) -> c11(MARK(from(from(0))))
   MARK(cons(from(from(nil)), z1)) -> c11(MARK(from(from(nil))))
   MARK(cons(s(s(y0)), z1)) -> c11(MARK(s(s(y0))))
   MARK(cons(s(cons(y0, y1)), z1)) -> c11(MARK(s(cons(y0, y1))))
   MARK(cons(s(first(y0, 0)), z1)) -> c11(MARK(s(first(y0, 0))))
   MARK(cons(s(first(y0, nil)), z1)) -> c11(MARK(s(first(y0, nil))))
   MARK(cons(s(first(y0, s(y1))), z1)) -> c11(MARK(s(first(y0, s(y1)))))
   MARK(cons(s(first(cons(y0, y1), y2)), z1)) -> c11(MARK(s(first(cons(y0, y1), y2))))
   MARK(cons(s(first(0, y0)), z1)) -> c11(MARK(s(first(0, y0))))
   MARK(cons(s(first(nil, y0)), z1)) -> c11(MARK(s(first(nil, y0))))
   MARK(cons(s(first(y0, first(y1, first(y2, y3)))), z1)) -> c11(MARK(s(first(y0, first(y1, first(y2, y3))))))
   MARK(cons(s(first(y0, first(y1, from(y2)))), z1)) -> c11(MARK(s(first(y0, first(y1, from(y2))))))
   MARK(cons(s(first(y0, first(y1, 0))), z1)) -> c11(MARK(s(first(y0, first(y1, 0)))))
   MARK(cons(s(first(y0, first(y1, nil))), z1)) -> c11(MARK(s(first(y0, first(y1, nil)))))
   MARK(cons(s(first(y0, first(y1, s(y2)))), z1)) -> c11(MARK(s(first(y0, first(y1, s(y2))))))
   MARK(cons(s(first(y0, first(y1, cons(y2, y3)))), z1)) -> c11(MARK(s(first(y0, first(y1, cons(y2, y3))))))
   MARK(cons(s(first(y0, first(first(y1, y2), y3))), z1)) -> c11(MARK(s(first(y0, first(first(y1, y2), y3)))))
   MARK(cons(s(first(y0, first(from(y1), y2))), z1)) -> c11(MARK(s(first(y0, first(from(y1), y2)))))
   MARK(cons(s(first(y0, first(0, y1))), z1)) -> c11(MARK(s(first(y0, first(0, y1)))))
   MARK(cons(s(first(y0, first(nil, y1))), z1)) -> c11(MARK(s(first(y0, first(nil, y1)))))
   MARK(cons(s(first(y0, first(s(y1), y2))), z1)) -> c11(MARK(s(first(y0, first(s(y1), y2)))))
   MARK(cons(s(first(y0, first(cons(y1, y2), y3))), z1)) -> c11(MARK(s(first(y0, first(cons(y1, y2), y3)))))
   MARK(cons(s(first(first(y0, y1), first(y2, y3))), z1)) -> c11(MARK(s(first(first(y0, y1), first(y2, y3)))))
   MARK(cons(s(first(from(y0), first(y1, y2))), z1)) -> c11(MARK(s(first(from(y0), first(y1, y2)))))
   MARK(cons(s(first(s(y0), first(y1, y2))), z1)) -> c11(MARK(s(first(s(y0), first(y1, y2)))))
   MARK(cons(s(first(y0, first(y1, y2))), z1)) -> c11(MARK(s(first(y0, first(y1, y2)))))
   MARK(cons(s(first(cons(y0, y1), first(y2, y3))), z1)) -> c11(MARK(s(first(cons(y0, y1), first(y2, y3)))))
   MARK(cons(s(first(y0, from(y1))), z1)) -> c11(MARK(s(first(y0, from(y1)))))
   MARK(cons(s(first(y0, from(first(y1, y2)))), z1)) -> c11(MARK(s(first(y0, from(first(y1, y2))))))
   MARK(cons(s(first(y0, from(from(y1)))), z1)) -> c11(MARK(s(first(y0, from(from(y1))))))
   MARK(cons(s(first(y0, from(0))), z1)) -> c11(MARK(s(first(y0, from(0)))))
   MARK(cons(s(first(y0, from(nil))), z1)) -> c11(MARK(s(first(y0, from(nil)))))
   MARK(cons(s(first(y0, from(s(y1)))), z1)) -> c11(MARK(s(first(y0, from(s(y1))))))
   MARK(cons(s(first(y0, from(cons(y1, y2)))), z1)) -> c11(MARK(s(first(y0, from(cons(y1, y2))))))
   MARK(cons(s(first(first(y0, y1), from(y2))), z1)) -> c11(MARK(s(first(first(y0, y1), from(y2)))))
   MARK(cons(s(first(from(y0), from(y1))), z1)) -> c11(MARK(s(first(from(y0), from(y1)))))
   MARK(cons(s(first(s(y0), from(y1))), z1)) -> c11(MARK(s(first(s(y0), from(y1)))))
   MARK(cons(s(first(cons(y0, y1), from(y2))), z1)) -> c11(MARK(s(first(cons(y0, y1), from(y2)))))
   MARK(cons(s(first(y0, cons(first(y1, y2), y3))), z1)) -> c11(MARK(s(first(y0, cons(first(y1, y2), y3)))))
   MARK(cons(s(first(y0, cons(from(y1), y2))), z1)) -> c11(MARK(s(first(y0, cons(from(y1), y2)))))
   MARK(cons(s(first(y0, cons(s(y1), y2))), z1)) -> c11(MARK(s(first(y0, cons(s(y1), y2)))))
   MARK(cons(s(first(y0, cons(cons(y1, y2), y3))), z1)) -> c11(MARK(s(first(y0, cons(cons(y1, y2), y3)))))
   MARK(cons(s(first(first(y0, y1), cons(y2, y3))), z1)) -> c11(MARK(s(first(first(y0, y1), cons(y2, y3)))))
   MARK(cons(s(first(from(y0), cons(y1, y2))), z1)) -> c11(MARK(s(first(from(y0), cons(y1, y2)))))
   MARK(cons(s(first(s(y0), cons(y1, y2))), z1)) -> c11(MARK(s(first(s(y0), cons(y1, y2)))))
   MARK(cons(s(first(cons(y0, y1), cons(y2, y3))), z1)) -> c11(MARK(s(first(cons(y0, y1), cons(y2, y3)))))
   MARK(cons(s(first(first(y0, first(y1, y2)), y3)), z1)) -> c11(MARK(s(first(first(y0, first(y1, y2)), y3))))
   MARK(cons(s(first(first(y0, from(y1)), y2)), z1)) -> c11(MARK(s(first(first(y0, from(y1)), y2))))
   MARK(cons(s(first(first(y0, 0), y1)), z1)) -> c11(MARK(s(first(first(y0, 0), y1))))
   MARK(cons(s(first(first(y0, nil), y1)), z1)) -> c11(MARK(s(first(first(y0, nil), y1))))
   MARK(cons(s(first(first(y0, s(y1)), y2)), z1)) -> c11(MARK(s(first(first(y0, s(y1)), y2))))
   MARK(cons(s(first(first(y0, cons(y1, y2)), y3)), z1)) -> c11(MARK(s(first(first(y0, cons(y1, y2)), y3))))
   MARK(cons(s(first(first(first(y0, y1), y2), y3)), z1)) -> c11(MARK(s(first(first(first(y0, y1), y2), y3))))
   MARK(cons(s(first(first(from(y0), y1), y2)), z1)) -> c11(MARK(s(first(first(from(y0), y1), y2))))
   MARK(cons(s(first(first(0, y0), y1)), z1)) -> c11(MARK(s(first(first(0, y0), y1))))
   MARK(cons(s(first(first(nil, y0), y1)), z1)) -> c11(MARK(s(first(first(nil, y0), y1))))
   MARK(cons(s(first(first(s(y0), y1), y2)), z1)) -> c11(MARK(s(first(first(s(y0), y1), y2))))
   MARK(cons(s(first(first(cons(y0, y1), y2), y3)), z1)) -> c11(MARK(s(first(first(cons(y0, y1), y2), y3))))
   MARK(cons(s(first(first(y0, y1), 0)), z1)) -> c11(MARK(s(first(first(y0, y1), 0))))
   MARK(cons(s(first(first(y0, y1), nil)), z1)) -> c11(MARK(s(first(first(y0, y1), nil))))
   MARK(cons(s(first(first(y0, y1), s(y2))), z1)) -> c11(MARK(s(first(first(y0, y1), s(y2)))))
   MARK(cons(s(first(first(y0, y1), y2)), z1)) -> c11(MARK(s(first(first(y0, y1), y2))))
   MARK(cons(s(first(from(first(y0, y1)), y2)), z1)) -> c11(MARK(s(first(from(first(y0, y1)), y2))))
   MARK(cons(s(first(from(from(y0)), y1)), z1)) -> c11(MARK(s(first(from(from(y0)), y1))))
   MARK(cons(s(first(from(s(y0)), y1)), z1)) -> c11(MARK(s(first(from(s(y0)), y1))))
   MARK(cons(s(first(from(cons(y0, y1)), y2)), z1)) -> c11(MARK(s(first(from(cons(y0, y1)), y2))))
   MARK(cons(s(first(from(y0), y1)), z1)) -> c11(MARK(s(first(from(y0), y1))))
   MARK(cons(s(first(from(y0), 0)), z1)) -> c11(MARK(s(first(from(y0), 0))))
   MARK(cons(s(first(from(y0), nil)), z1)) -> c11(MARK(s(first(from(y0), nil))))
   MARK(cons(s(first(from(y0), s(y1))), z1)) -> c11(MARK(s(first(from(y0), s(y1)))))
   MARK(cons(s(first(s(first(y0, y1)), y2)), z1)) -> c11(MARK(s(first(s(first(y0, y1)), y2))))
   MARK(cons(s(first(s(from(y0)), y1)), z1)) -> c11(MARK(s(first(s(from(y0)), y1))))
   MARK(cons(s(first(s(0), y0)), z1)) -> c11(MARK(s(first(s(0), y0))))
   MARK(cons(s(first(s(nil), y0)), z1)) -> c11(MARK(s(first(s(nil), y0))))
   MARK(cons(s(first(s(s(y0)), y1)), z1)) -> c11(MARK(s(first(s(s(y0)), y1))))
   MARK(cons(s(first(s(cons(y0, y1)), y2)), z1)) -> c11(MARK(s(first(s(cons(y0, y1)), y2))))
   MARK(cons(s(first(s(y0), y1)), z1)) -> c11(MARK(s(first(s(y0), y1))))
   MARK(cons(s(first(s(y0), 0)), z1)) -> c11(MARK(s(first(s(y0), 0))))
   MARK(cons(s(first(s(y0), nil)), z1)) -> c11(MARK(s(first(s(y0), nil))))
   MARK(cons(s(first(s(y0), s(y1))), z1)) -> c11(MARK(s(first(s(y0), s(y1)))))
   MARK(cons(s(first(0, first(y0, y1))), z1)) -> c11(MARK(s(first(0, first(y0, y1)))))
   MARK(cons(s(first(nil, first(y0, y1))), z1)) -> c11(MARK(s(first(nil, first(y0, y1)))))
   MARK(cons(s(first(0, from(y0))), z1)) -> c11(MARK(s(first(0, from(y0)))))
   MARK(cons(s(first(nil, from(y0))), z1)) -> c11(MARK(s(first(nil, from(y0)))))
   MARK(cons(s(first(y0, cons(y1, y2))), z1)) -> c11(MARK(s(first(y0, cons(y1, y2)))))
   MARK(cons(s(first(0, cons(y0, y1))), z1)) -> c11(MARK(s(first(0, cons(y0, y1)))))
   MARK(cons(s(first(nil, cons(y0, y1))), z1)) -> c11(MARK(s(first(nil, cons(y0, y1)))))
   MARK(cons(s(first(from(0), y0)), z1)) -> c11(MARK(s(first(from(0), y0))))
   MARK(cons(s(first(from(nil), y0)), z1)) -> c11(MARK(s(first(from(nil), y0))))
   MARK(cons(s(first(y0, cons(0, y1))), z1)) -> c11(MARK(s(first(y0, cons(0, y1)))))
   MARK(cons(s(first(y0, cons(nil, y1))), z1)) -> c11(MARK(s(first(y0, cons(nil, y1)))))
   MARK(cons(s(from(s(y0))), z1)) -> c11(MARK(s(from(s(y0)))))
   MARK(cons(s(from(cons(y0, y1))), z1)) -> c11(MARK(s(from(cons(y0, y1)))))
   MARK(cons(s(from(first(y0, y1))), z1)) -> c11(MARK(s(from(first(y0, y1)))))
   MARK(cons(s(from(first(y0, first(y1, y2)))), z1)) -> c11(MARK(s(from(first(y0, first(y1, y2))))))
   MARK(cons(s(from(first(y0, from(y1)))), z1)) -> c11(MARK(s(from(first(y0, from(y1))))))
   MARK(cons(s(from(first(y0, 0))), z1)) -> c11(MARK(s(from(first(y0, 0)))))
   MARK(cons(s(from(first(y0, nil))), z1)) -> c11(MARK(s(from(first(y0, nil)))))
   MARK(cons(s(from(first(y0, s(y1)))), z1)) -> c11(MARK(s(from(first(y0, s(y1))))))
   MARK(cons(s(from(first(y0, cons(y1, y2)))), z1)) -> c11(MARK(s(from(first(y0, cons(y1, y2))))))
   MARK(cons(s(from(first(first(y0, y1), y2))), z1)) -> c11(MARK(s(from(first(first(y0, y1), y2)))))
   MARK(cons(s(from(first(from(y0), y1))), z1)) -> c11(MARK(s(from(first(from(y0), y1)))))
   MARK(cons(s(from(first(0, y0))), z1)) -> c11(MARK(s(from(first(0, y0)))))
   MARK(cons(s(from(first(nil, y0))), z1)) -> c11(MARK(s(from(first(nil, y0)))))
   MARK(cons(s(from(first(s(y0), y1))), z1)) -> c11(MARK(s(from(first(s(y0), y1)))))
   MARK(cons(s(from(first(cons(y0, y1), y2))), z1)) -> c11(MARK(s(from(first(cons(y0, y1), y2)))))
   MARK(cons(s(from(from(y0))), z1)) -> c11(MARK(s(from(from(y0)))))
   MARK(cons(s(from(from(first(y0, y1)))), z1)) -> c11(MARK(s(from(from(first(y0, y1))))))
   MARK(cons(s(from(from(from(y0)))), z1)) -> c11(MARK(s(from(from(from(y0))))))
   MARK(cons(s(from(from(s(y0)))), z1)) -> c11(MARK(s(from(from(s(y0))))))
   MARK(cons(s(from(from(cons(y0, y1)))), z1)) -> c11(MARK(s(from(from(cons(y0, y1))))))
   MARK(cons(s(from(from(0))), z1)) -> c11(MARK(s(from(from(0)))))
   MARK(cons(s(from(from(nil))), z1)) -> c11(MARK(s(from(from(nil)))))
S tuples:
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
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   MARK(cons(from(from(0)), z1)) -> c11(MARK(from(from(0))))
   MARK(cons(from(from(nil)), z1)) -> c11(MARK(from(from(nil))))
   MARK(cons(s(s(y0)), z1)) -> c11(MARK(s(s(y0))))
   MARK(cons(s(cons(y0, y1)), z1)) -> c11(MARK(s(cons(y0, y1))))
   MARK(cons(s(first(y0, 0)), z1)) -> c11(MARK(s(first(y0, 0))))
   MARK(cons(s(first(y0, nil)), z1)) -> c11(MARK(s(first(y0, nil))))
   MARK(cons(s(first(y0, s(y1))), z1)) -> c11(MARK(s(first(y0, s(y1)))))
   MARK(cons(s(first(cons(y0, y1), y2)), z1)) -> c11(MARK(s(first(cons(y0, y1), y2))))
   MARK(cons(s(first(0, y0)), z1)) -> c11(MARK(s(first(0, y0))))
   MARK(cons(s(first(nil, y0)), z1)) -> c11(MARK(s(first(nil, y0))))
   MARK(cons(s(first(y0, first(y1, first(y2, y3)))), z1)) -> c11(MARK(s(first(y0, first(y1, first(y2, y3))))))
   MARK(cons(s(first(y0, first(y1, from(y2)))), z1)) -> c11(MARK(s(first(y0, first(y1, from(y2))))))
   MARK(cons(s(first(y0, first(y1, 0))), z1)) -> c11(MARK(s(first(y0, first(y1, 0)))))
   MARK(cons(s(first(y0, first(y1, nil))), z1)) -> c11(MARK(s(first(y0, first(y1, nil)))))
   MARK(cons(s(first(y0, first(y1, s(y2)))), z1)) -> c11(MARK(s(first(y0, first(y1, s(y2))))))
   MARK(cons(s(first(y0, first(y1, cons(y2, y3)))), z1)) -> c11(MARK(s(first(y0, first(y1, cons(y2, y3))))))
   MARK(cons(s(first(y0, first(first(y1, y2), y3))), z1)) -> c11(MARK(s(first(y0, first(first(y1, y2), y3)))))
   MARK(cons(s(first(y0, first(from(y1), y2))), z1)) -> c11(MARK(s(first(y0, first(from(y1), y2)))))
   MARK(cons(s(first(y0, first(0, y1))), z1)) -> c11(MARK(s(first(y0, first(0, y1)))))
   MARK(cons(s(first(y0, first(nil, y1))), z1)) -> c11(MARK(s(first(y0, first(nil, y1)))))
   MARK(cons(s(first(y0, first(s(y1), y2))), z1)) -> c11(MARK(s(first(y0, first(s(y1), y2)))))
   MARK(cons(s(first(y0, first(cons(y1, y2), y3))), z1)) -> c11(MARK(s(first(y0, first(cons(y1, y2), y3)))))
   MARK(cons(s(first(first(y0, y1), first(y2, y3))), z1)) -> c11(MARK(s(first(first(y0, y1), first(y2, y3)))))
   MARK(cons(s(first(from(y0), first(y1, y2))), z1)) -> c11(MARK(s(first(from(y0), first(y1, y2)))))
   MARK(cons(s(first(s(y0), first(y1, y2))), z1)) -> c11(MARK(s(first(s(y0), first(y1, y2)))))
   MARK(cons(s(first(y0, first(y1, y2))), z1)) -> c11(MARK(s(first(y0, first(y1, y2)))))
   MARK(cons(s(first(cons(y0, y1), first(y2, y3))), z1)) -> c11(MARK(s(first(cons(y0, y1), first(y2, y3)))))
   MARK(cons(s(first(y0, from(y1))), z1)) -> c11(MARK(s(first(y0, from(y1)))))
   MARK(cons(s(first(y0, from(first(y1, y2)))), z1)) -> c11(MARK(s(first(y0, from(first(y1, y2))))))
   MARK(cons(s(first(y0, from(from(y1)))), z1)) -> c11(MARK(s(first(y0, from(from(y1))))))
   MARK(cons(s(first(y0, from(0))), z1)) -> c11(MARK(s(first(y0, from(0)))))
   MARK(cons(s(first(y0, from(nil))), z1)) -> c11(MARK(s(first(y0, from(nil)))))
   MARK(cons(s(first(y0, from(s(y1)))), z1)) -> c11(MARK(s(first(y0, from(s(y1))))))
   MARK(cons(s(first(y0, from(cons(y1, y2)))), z1)) -> c11(MARK(s(first(y0, from(cons(y1, y2))))))
   MARK(cons(s(first(first(y0, y1), from(y2))), z1)) -> c11(MARK(s(first(first(y0, y1), from(y2)))))
   MARK(cons(s(first(from(y0), from(y1))), z1)) -> c11(MARK(s(first(from(y0), from(y1)))))
   MARK(cons(s(first(s(y0), from(y1))), z1)) -> c11(MARK(s(first(s(y0), from(y1)))))
   MARK(cons(s(first(cons(y0, y1), from(y2))), z1)) -> c11(MARK(s(first(cons(y0, y1), from(y2)))))
   MARK(cons(s(first(y0, cons(first(y1, y2), y3))), z1)) -> c11(MARK(s(first(y0, cons(first(y1, y2), y3)))))
   MARK(cons(s(first(y0, cons(from(y1), y2))), z1)) -> c11(MARK(s(first(y0, cons(from(y1), y2)))))
   MARK(cons(s(first(y0, cons(s(y1), y2))), z1)) -> c11(MARK(s(first(y0, cons(s(y1), y2)))))
   MARK(cons(s(first(y0, cons(cons(y1, y2), y3))), z1)) -> c11(MARK(s(first(y0, cons(cons(y1, y2), y3)))))
   MARK(cons(s(first(first(y0, y1), cons(y2, y3))), z1)) -> c11(MARK(s(first(first(y0, y1), cons(y2, y3)))))
   MARK(cons(s(first(from(y0), cons(y1, y2))), z1)) -> c11(MARK(s(first(from(y0), cons(y1, y2)))))
   MARK(cons(s(first(s(y0), cons(y1, y2))), z1)) -> c11(MARK(s(first(s(y0), cons(y1, y2)))))
   MARK(cons(s(first(cons(y0, y1), cons(y2, y3))), z1)) -> c11(MARK(s(first(cons(y0, y1), cons(y2, y3)))))
   MARK(cons(s(first(first(y0, first(y1, y2)), y3)), z1)) -> c11(MARK(s(first(first(y0, first(y1, y2)), y3))))
   MARK(cons(s(first(first(y0, from(y1)), y2)), z1)) -> c11(MARK(s(first(first(y0, from(y1)), y2))))
   MARK(cons(s(first(first(y0, 0), y1)), z1)) -> c11(MARK(s(first(first(y0, 0), y1))))
   MARK(cons(s(first(first(y0, nil), y1)), z1)) -> c11(MARK(s(first(first(y0, nil), y1))))
   MARK(cons(s(first(first(y0, s(y1)), y2)), z1)) -> c11(MARK(s(first(first(y0, s(y1)), y2))))
   MARK(cons(s(first(first(y0, cons(y1, y2)), y3)), z1)) -> c11(MARK(s(first(first(y0, cons(y1, y2)), y3))))
   MARK(cons(s(first(first(first(y0, y1), y2), y3)), z1)) -> c11(MARK(s(first(first(first(y0, y1), y2), y3))))
   MARK(cons(s(first(first(from(y0), y1), y2)), z1)) -> c11(MARK(s(first(first(from(y0), y1), y2))))
   MARK(cons(s(first(first(0, y0), y1)), z1)) -> c11(MARK(s(first(first(0, y0), y1))))
   MARK(cons(s(first(first(nil, y0), y1)), z1)) -> c11(MARK(s(first(first(nil, y0), y1))))
   MARK(cons(s(first(first(s(y0), y1), y2)), z1)) -> c11(MARK(s(first(first(s(y0), y1), y2))))
   MARK(cons(s(first(first(cons(y0, y1), y2), y3)), z1)) -> c11(MARK(s(first(first(cons(y0, y1), y2), y3))))
   MARK(cons(s(first(first(y0, y1), 0)), z1)) -> c11(MARK(s(first(first(y0, y1), 0))))
   MARK(cons(s(first(first(y0, y1), nil)), z1)) -> c11(MARK(s(first(first(y0, y1), nil))))
   MARK(cons(s(first(first(y0, y1), s(y2))), z1)) -> c11(MARK(s(first(first(y0, y1), s(y2)))))
   MARK(cons(s(first(first(y0, y1), y2)), z1)) -> c11(MARK(s(first(first(y0, y1), y2))))
   MARK(cons(s(first(from(first(y0, y1)), y2)), z1)) -> c11(MARK(s(first(from(first(y0, y1)), y2))))
   MARK(cons(s(first(from(from(y0)), y1)), z1)) -> c11(MARK(s(first(from(from(y0)), y1))))
   MARK(cons(s(first(from(s(y0)), y1)), z1)) -> c11(MARK(s(first(from(s(y0)), y1))))
   MARK(cons(s(first(from(cons(y0, y1)), y2)), z1)) -> c11(MARK(s(first(from(cons(y0, y1)), y2))))
   MARK(cons(s(first(from(y0), y1)), z1)) -> c11(MARK(s(first(from(y0), y1))))
   MARK(cons(s(first(from(y0), 0)), z1)) -> c11(MARK(s(first(from(y0), 0))))
   MARK(cons(s(first(from(y0), nil)), z1)) -> c11(MARK(s(first(from(y0), nil))))
   MARK(cons(s(first(from(y0), s(y1))), z1)) -> c11(MARK(s(first(from(y0), s(y1)))))
   MARK(cons(s(first(s(first(y0, y1)), y2)), z1)) -> c11(MARK(s(first(s(first(y0, y1)), y2))))
   MARK(cons(s(first(s(from(y0)), y1)), z1)) -> c11(MARK(s(first(s(from(y0)), y1))))
   MARK(cons(s(first(s(0), y0)), z1)) -> c11(MARK(s(first(s(0), y0))))
   MARK(cons(s(first(s(nil), y0)), z1)) -> c11(MARK(s(first(s(nil), y0))))
   MARK(cons(s(first(s(s(y0)), y1)), z1)) -> c11(MARK(s(first(s(s(y0)), y1))))
   MARK(cons(s(first(s(cons(y0, y1)), y2)), z1)) -> c11(MARK(s(first(s(cons(y0, y1)), y2))))
   MARK(cons(s(first(s(y0), y1)), z1)) -> c11(MARK(s(first(s(y0), y1))))
   MARK(cons(s(first(s(y0), 0)), z1)) -> c11(MARK(s(first(s(y0), 0))))
   MARK(cons(s(first(s(y0), nil)), z1)) -> c11(MARK(s(first(s(y0), nil))))
   MARK(cons(s(first(s(y0), s(y1))), z1)) -> c11(MARK(s(first(s(y0), s(y1)))))
   MARK(cons(s(first(0, first(y0, y1))), z1)) -> c11(MARK(s(first(0, first(y0, y1)))))
   MARK(cons(s(first(nil, first(y0, y1))), z1)) -> c11(MARK(s(first(nil, first(y0, y1)))))
   MARK(cons(s(first(0, from(y0))), z1)) -> c11(MARK(s(first(0, from(y0)))))
   MARK(cons(s(first(nil, from(y0))), z1)) -> c11(MARK(s(first(nil, from(y0)))))
   MARK(cons(s(first(y0, cons(y1, y2))), z1)) -> c11(MARK(s(first(y0, cons(y1, y2)))))
   MARK(cons(s(first(0, cons(y0, y1))), z1)) -> c11(MARK(s(first(0, cons(y0, y1)))))
   MARK(cons(s(first(nil, cons(y0, y1))), z1)) -> c11(MARK(s(first(nil, cons(y0, y1)))))
   MARK(cons(s(first(from(0), y0)), z1)) -> c11(MARK(s(first(from(0), y0))))
   MARK(cons(s(first(from(nil), y0)), z1)) -> c11(MARK(s(first(from(nil), y0))))
   MARK(cons(s(first(y0, cons(0, y1))), z1)) -> c11(MARK(s(first(y0, cons(0, y1)))))
   MARK(cons(s(first(y0, cons(nil, y1))), z1)) -> c11(MARK(s(first(y0, cons(nil, y1)))))
   MARK(cons(s(from(s(y0))), z1)) -> c11(MARK(s(from(s(y0)))))
   MARK(cons(s(from(cons(y0, y1))), z1)) -> c11(MARK(s(from(cons(y0, y1)))))
   MARK(cons(s(from(first(y0, y1))), z1)) -> c11(MARK(s(from(first(y0, y1)))))
   MARK(cons(s(from(first(y0, first(y1, y2)))), z1)) -> c11(MARK(s(from(first(y0, first(y1, y2))))))
   MARK(cons(s(from(first(y0, from(y1)))), z1)) -> c11(MARK(s(from(first(y0, from(y1))))))
   MARK(cons(s(from(first(y0, 0))), z1)) -> c11(MARK(s(from(first(y0, 0)))))
   MARK(cons(s(from(first(y0, nil))), z1)) -> c11(MARK(s(from(first(y0, nil)))))
   MARK(cons(s(from(first(y0, s(y1)))), z1)) -> c11(MARK(s(from(first(y0, s(y1))))))
   MARK(cons(s(from(first(y0, cons(y1, y2)))), z1)) -> c11(MARK(s(from(first(y0, cons(y1, y2))))))
   MARK(cons(s(from(first(first(y0, y1), y2))), z1)) -> c11(MARK(s(from(first(first(y0, y1), y2)))))
   MARK(cons(s(from(first(from(y0), y1))), z1)) -> c11(MARK(s(from(first(from(y0), y1)))))
   MARK(cons(s(from(first(0, y0))), z1)) -> c11(MARK(s(from(first(0, y0)))))
   MARK(cons(s(from(first(nil, y0))), z1)) -> c11(MARK(s(from(first(nil, y0)))))
   MARK(cons(s(from(first(s(y0), y1))), z1)) -> c11(MARK(s(from(first(s(y0), y1)))))
   MARK(cons(s(from(first(cons(y0, y1), y2))), z1)) -> c11(MARK(s(from(first(cons(y0, y1), y2)))))
   MARK(cons(s(from(from(y0))), z1)) -> c11(MARK(s(from(from(y0)))))
   MARK(cons(s(from(from(first(y0, y1)))), z1)) -> c11(MARK(s(from(from(first(y0, y1))))))
   MARK(cons(s(from(from(from(y0)))), z1)) -> c11(MARK(s(from(from(from(y0))))))
   MARK(cons(s(from(from(s(y0)))), z1)) -> c11(MARK(s(from(from(s(y0))))))
   MARK(cons(s(from(from(cons(y0, y1)))), z1)) -> c11(MARK(s(from(from(cons(y0, y1))))))
   MARK(cons(s(from(from(0))), z1)) -> c11(MARK(s(from(from(0)))))
   MARK(cons(s(from(from(nil))), z1)) -> c11(MARK(s(from(from(nil)))))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   MARK_1, A__FIRST_2, A__FROM_1

Compound Symbols:   c5_1, c6_1, c5_2, c6_2, c1_1, c3_1, c7_2, c7_1, c10_1, c11_1


----------------------------------------

(121) CdtLeafRemovalProof (BOTH BOUNDS(ID, ID))
Removed 2 trailing nodes:
   MARK(first(x0, cons(0, x2))) -> c6(MARK(cons(0, x2)))
   MARK(first(x0, cons(nil, x2))) -> c6(MARK(cons(nil, x2)))

----------------------------------------

(122)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
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   MARK(cons(s(first(from(y0), from(y1))), z1)) -> c11(MARK(s(first(from(y0), from(y1)))))
   MARK(cons(s(first(s(y0), from(y1))), z1)) -> c11(MARK(s(first(s(y0), from(y1)))))
   MARK(cons(s(first(cons(y0, y1), from(y2))), z1)) -> c11(MARK(s(first(cons(y0, y1), from(y2)))))
   MARK(cons(s(first(y0, cons(first(y1, y2), y3))), z1)) -> c11(MARK(s(first(y0, cons(first(y1, y2), y3)))))
   MARK(cons(s(first(y0, cons(from(y1), y2))), z1)) -> c11(MARK(s(first(y0, cons(from(y1), y2)))))
   MARK(cons(s(first(y0, cons(s(y1), y2))), z1)) -> c11(MARK(s(first(y0, cons(s(y1), y2)))))
   MARK(cons(s(first(y0, cons(cons(y1, y2), y3))), z1)) -> c11(MARK(s(first(y0, cons(cons(y1, y2), y3)))))
   MARK(cons(s(first(first(y0, y1), cons(y2, y3))), z1)) -> c11(MARK(s(first(first(y0, y1), cons(y2, y3)))))
   MARK(cons(s(first(from(y0), cons(y1, y2))), z1)) -> c11(MARK(s(first(from(y0), cons(y1, y2)))))
   MARK(cons(s(first(s(y0), cons(y1, y2))), z1)) -> c11(MARK(s(first(s(y0), cons(y1, y2)))))
   MARK(cons(s(first(cons(y0, y1), cons(y2, y3))), z1)) -> c11(MARK(s(first(cons(y0, y1), cons(y2, y3)))))
   MARK(cons(s(first(first(y0, first(y1, y2)), y3)), z1)) -> c11(MARK(s(first(first(y0, first(y1, y2)), y3))))
   MARK(cons(s(first(first(y0, from(y1)), y2)), z1)) -> c11(MARK(s(first(first(y0, from(y1)), y2))))
   MARK(cons(s(first(first(y0, 0), y1)), z1)) -> c11(MARK(s(first(first(y0, 0), y1))))
   MARK(cons(s(first(first(y0, nil), y1)), z1)) -> c11(MARK(s(first(first(y0, nil), y1))))
   MARK(cons(s(first(first(y0, s(y1)), y2)), z1)) -> c11(MARK(s(first(first(y0, s(y1)), y2))))
   MARK(cons(s(first(first(y0, cons(y1, y2)), y3)), z1)) -> c11(MARK(s(first(first(y0, cons(y1, y2)), y3))))
   MARK(cons(s(first(first(first(y0, y1), y2), y3)), z1)) -> c11(MARK(s(first(first(first(y0, y1), y2), y3))))
   MARK(cons(s(first(first(from(y0), y1), y2)), z1)) -> c11(MARK(s(first(first(from(y0), y1), y2))))
   MARK(cons(s(first(first(0, y0), y1)), z1)) -> c11(MARK(s(first(first(0, y0), y1))))
   MARK(cons(s(first(first(nil, y0), y1)), z1)) -> c11(MARK(s(first(first(nil, y0), y1))))
   MARK(cons(s(first(first(s(y0), y1), y2)), z1)) -> c11(MARK(s(first(first(s(y0), y1), y2))))
   MARK(cons(s(first(first(cons(y0, y1), y2), y3)), z1)) -> c11(MARK(s(first(first(cons(y0, y1), y2), y3))))
   MARK(cons(s(first(first(y0, y1), 0)), z1)) -> c11(MARK(s(first(first(y0, y1), 0))))
   MARK(cons(s(first(first(y0, y1), nil)), z1)) -> c11(MARK(s(first(first(y0, y1), nil))))
   MARK(cons(s(first(first(y0, y1), s(y2))), z1)) -> c11(MARK(s(first(first(y0, y1), s(y2)))))
   MARK(cons(s(first(first(y0, y1), y2)), z1)) -> c11(MARK(s(first(first(y0, y1), y2))))
   MARK(cons(s(first(from(first(y0, y1)), y2)), z1)) -> c11(MARK(s(first(from(first(y0, y1)), y2))))
   MARK(cons(s(first(from(from(y0)), y1)), z1)) -> c11(MARK(s(first(from(from(y0)), y1))))
   MARK(cons(s(first(from(s(y0)), y1)), z1)) -> c11(MARK(s(first(from(s(y0)), y1))))
   MARK(cons(s(first(from(cons(y0, y1)), y2)), z1)) -> c11(MARK(s(first(from(cons(y0, y1)), y2))))
   MARK(cons(s(first(from(y0), y1)), z1)) -> c11(MARK(s(first(from(y0), y1))))
   MARK(cons(s(first(from(y0), 0)), z1)) -> c11(MARK(s(first(from(y0), 0))))
   MARK(cons(s(first(from(y0), nil)), z1)) -> c11(MARK(s(first(from(y0), nil))))
   MARK(cons(s(first(from(y0), s(y1))), z1)) -> c11(MARK(s(first(from(y0), s(y1)))))
   MARK(cons(s(first(s(first(y0, y1)), y2)), z1)) -> c11(MARK(s(first(s(first(y0, y1)), y2))))
   MARK(cons(s(first(s(from(y0)), y1)), z1)) -> c11(MARK(s(first(s(from(y0)), y1))))
   MARK(cons(s(first(s(0), y0)), z1)) -> c11(MARK(s(first(s(0), y0))))
   MARK(cons(s(first(s(nil), y0)), z1)) -> c11(MARK(s(first(s(nil), y0))))
   MARK(cons(s(first(s(s(y0)), y1)), z1)) -> c11(MARK(s(first(s(s(y0)), y1))))
   MARK(cons(s(first(s(cons(y0, y1)), y2)), z1)) -> c11(MARK(s(first(s(cons(y0, y1)), y2))))
   MARK(cons(s(first(s(y0), y1)), z1)) -> c11(MARK(s(first(s(y0), y1))))
   MARK(cons(s(first(s(y0), 0)), z1)) -> c11(MARK(s(first(s(y0), 0))))
   MARK(cons(s(first(s(y0), nil)), z1)) -> c11(MARK(s(first(s(y0), nil))))
   MARK(cons(s(first(s(y0), s(y1))), z1)) -> c11(MARK(s(first(s(y0), s(y1)))))
   MARK(cons(s(first(0, first(y0, y1))), z1)) -> c11(MARK(s(first(0, first(y0, y1)))))
   MARK(cons(s(first(nil, first(y0, y1))), z1)) -> c11(MARK(s(first(nil, first(y0, y1)))))
   MARK(cons(s(first(0, from(y0))), z1)) -> c11(MARK(s(first(0, from(y0)))))
   MARK(cons(s(first(nil, from(y0))), z1)) -> c11(MARK(s(first(nil, from(y0)))))
   MARK(cons(s(first(y0, cons(y1, y2))), z1)) -> c11(MARK(s(first(y0, cons(y1, y2)))))
   MARK(cons(s(first(0, cons(y0, y1))), z1)) -> c11(MARK(s(first(0, cons(y0, y1)))))
   MARK(cons(s(first(nil, cons(y0, y1))), z1)) -> c11(MARK(s(first(nil, cons(y0, y1)))))
   MARK(cons(s(first(from(0), y0)), z1)) -> c11(MARK(s(first(from(0), y0))))
   MARK(cons(s(first(from(nil), y0)), z1)) -> c11(MARK(s(first(from(nil), y0))))
   MARK(cons(s(first(y0, cons(0, y1))), z1)) -> c11(MARK(s(first(y0, cons(0, y1)))))
   MARK(cons(s(first(y0, cons(nil, y1))), z1)) -> c11(MARK(s(first(y0, cons(nil, y1)))))
   MARK(cons(s(from(s(y0))), z1)) -> c11(MARK(s(from(s(y0)))))
   MARK(cons(s(from(cons(y0, y1))), z1)) -> c11(MARK(s(from(cons(y0, y1)))))
   MARK(cons(s(from(first(y0, y1))), z1)) -> c11(MARK(s(from(first(y0, y1)))))
   MARK(cons(s(from(first(y0, first(y1, y2)))), z1)) -> c11(MARK(s(from(first(y0, first(y1, y2))))))
   MARK(cons(s(from(first(y0, from(y1)))), z1)) -> c11(MARK(s(from(first(y0, from(y1))))))
   MARK(cons(s(from(first(y0, 0))), z1)) -> c11(MARK(s(from(first(y0, 0)))))
   MARK(cons(s(from(first(y0, nil))), z1)) -> c11(MARK(s(from(first(y0, nil)))))
   MARK(cons(s(from(first(y0, s(y1)))), z1)) -> c11(MARK(s(from(first(y0, s(y1))))))
   MARK(cons(s(from(first(y0, cons(y1, y2)))), z1)) -> c11(MARK(s(from(first(y0, cons(y1, y2))))))
   MARK(cons(s(from(first(first(y0, y1), y2))), z1)) -> c11(MARK(s(from(first(first(y0, y1), y2)))))
   MARK(cons(s(from(first(from(y0), y1))), z1)) -> c11(MARK(s(from(first(from(y0), y1)))))
   MARK(cons(s(from(first(0, y0))), z1)) -> c11(MARK(s(from(first(0, y0)))))
   MARK(cons(s(from(first(nil, y0))), z1)) -> c11(MARK(s(from(first(nil, y0)))))
   MARK(cons(s(from(first(s(y0), y1))), z1)) -> c11(MARK(s(from(first(s(y0), y1)))))
   MARK(cons(s(from(first(cons(y0, y1), y2))), z1)) -> c11(MARK(s(from(first(cons(y0, y1), y2)))))
   MARK(cons(s(from(from(y0))), z1)) -> c11(MARK(s(from(from(y0)))))
   MARK(cons(s(from(from(first(y0, y1)))), z1)) -> c11(MARK(s(from(from(first(y0, y1))))))
   MARK(cons(s(from(from(from(y0)))), z1)) -> c11(MARK(s(from(from(from(y0))))))
   MARK(cons(s(from(from(s(y0)))), z1)) -> c11(MARK(s(from(from(s(y0))))))
   MARK(cons(s(from(from(cons(y0, y1)))), z1)) -> c11(MARK(s(from(from(cons(y0, y1))))))
   MARK(cons(s(from(from(0))), z1)) -> c11(MARK(s(from(from(0)))))
   MARK(cons(s(from(from(nil))), z1)) -> c11(MARK(s(from(from(nil)))))
S tuples:
   MARK(first(x0, 0)) -> c5(MARK(x0))
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
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   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
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   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
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   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
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   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
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   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
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   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
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   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
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   MARK(first(first(x0, x1), x2)) -> c6(MARK(x2))
   MARK(first(from(first(z0, z1)), x1)) -> c6(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(from(from(z0)), x1)) -> c6(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(0), x1)) -> c6(A__FIRST(a__from(0), mark(x1)), MARK(x1))
   MARK(first(from(nil), x1)) -> c6(A__FIRST(a__from(nil), mark(x1)), MARK(x1))
   MARK(first(from(s(z0)), x1)) -> c6(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(cons(z0, z1)), x1)) -> c6(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(x1))
   MARK(first(from(x0), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(from(x0), x1)) -> c6(MARK(x1))
   MARK(first(s(first(z0, z1)), x1)) -> c6(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(s(from(z0)), x1)) -> c6(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(0), x1)) -> c6(A__FIRST(s(0), mark(x1)), MARK(x1))
   MARK(first(s(nil), x1)) -> c6(A__FIRST(s(nil), mark(x1)), MARK(x1))
   MARK(first(s(s(z0)), x1)) -> c6(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(cons(z0, z1)), x1)) -> c6(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(x1))
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   A__FIRST(s(z0), cons(s(y0), z2)) -> c1(MARK(s(y0)))
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   A__FIRST(s(z0), cons(first(y0, 0), z2)) -> c1(MARK(first(y0, 0)))
   A__FIRST(s(z0), cons(first(y0, nil), z2)) -> c1(MARK(first(y0, nil)))
   A__FIRST(s(z0), cons(first(y0, s(y1)), z2)) -> c1(MARK(first(y0, s(y1))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), y2), z2)) -> c1(MARK(first(cons(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(0, y0), z2)) -> c1(MARK(first(0, y0)))
   A__FIRST(s(z0), cons(first(nil, y0), z2)) -> c1(MARK(first(nil, y0)))
   A__FIRST(s(z0), cons(first(y0, first(y1, first(y2, y3))), z2)) -> c1(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FIRST(s(z0), cons(first(y0, first(y1, from(y2))), z2)) -> c1(MARK(first(y0, first(y1, from(y2)))))
   A__FIRST(s(z0), cons(first(y0, first(y1, 0)), z2)) -> c1(MARK(first(y0, first(y1, 0))))
   A__FIRST(s(z0), cons(first(y0, first(y1, nil)), z2)) -> c1(MARK(first(y0, first(y1, nil))))
   A__FIRST(s(z0), cons(first(y0, first(y1, s(y2))), z2)) -> c1(MARK(first(y0, first(y1, s(y2)))))
   A__FIRST(s(z0), cons(first(y0, first(y1, cons(y2, y3))), z2)) -> c1(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FIRST(s(z0), cons(first(y0, first(first(y1, y2), y3)), z2)) -> c1(MARK(first(y0, first(first(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(y0, first(from(y1), y2)), z2)) -> c1(MARK(first(y0, first(from(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, first(0, y1)), z2)) -> c1(MARK(first(y0, first(0, y1))))
   A__FIRST(s(z0), cons(first(y0, first(nil, y1)), z2)) -> c1(MARK(first(y0, first(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, first(s(y1), y2)), z2)) -> c1(MARK(first(y0, first(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, first(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), first(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), first(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), first(y1, y2)), z2)) -> c1(MARK(first(from(y0), first(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), first(y1, y2)), z2)) -> c1(MARK(first(s(y0), first(y1, y2))))
   A__FIRST(s(z0), cons(first(y0, first(y1, y2)), z2)) -> c1(MARK(first(y0, first(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), first(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FIRST(s(z0), cons(first(y0, from(y1)), z2)) -> c1(MARK(first(y0, from(y1))))
   A__FIRST(s(z0), cons(first(y0, from(first(y1, y2))), z2)) -> c1(MARK(first(y0, from(first(y1, y2)))))
   A__FIRST(s(z0), cons(first(y0, from(from(y1))), z2)) -> c1(MARK(first(y0, from(from(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(0)), z2)) -> c1(MARK(first(y0, from(0))))
   A__FIRST(s(z0), cons(first(y0, from(nil)), z2)) -> c1(MARK(first(y0, from(nil))))
   A__FIRST(s(z0), cons(first(y0, from(s(y1))), z2)) -> c1(MARK(first(y0, from(s(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(cons(y1, y2))), z2)) -> c1(MARK(first(y0, from(cons(y1, y2)))))
   A__FIRST(s(z0), cons(first(first(y0, y1), from(y2)), z2)) -> c1(MARK(first(first(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(from(y0), from(y1)), z2)) -> c1(MARK(first(from(y0), from(y1))))
   A__FIRST(s(z0), cons(first(s(y0), from(y1)), z2)) -> c1(MARK(first(s(y0), from(y1))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), from(y2)), z2)) -> c1(MARK(first(cons(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(y0, cons(first(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(y0, cons(from(y1), y2)), z2)) -> c1(MARK(first(y0, cons(from(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(0, y1)), z2)) -> c1(MARK(first(y0, cons(0, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(nil, y1)), z2)) -> c1(MARK(first(y0, cons(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(s(y1), y2)), z2)) -> c1(MARK(first(y0, cons(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), cons(y1, y2)), z2)) -> c1(MARK(first(from(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), cons(y1, y2)), z2)) -> c1(MARK(first(s(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(first(y0, first(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(y0, from(y1)), y2), z2)) -> c1(MARK(first(first(y0, from(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, 0), y1), z2)) -> c1(MARK(first(first(y0, 0), y1)))
   A__FIRST(s(z0), cons(first(first(y0, nil), y1), z2)) -> c1(MARK(first(first(y0, nil), y1)))
   A__FIRST(s(z0), cons(first(first(y0, s(y1)), y2), z2)) -> c1(MARK(first(first(y0, s(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, cons(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(first(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(first(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(from(y0), y1), y2), z2)) -> c1(MARK(first(first(from(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(0, y0), y1), z2)) -> c1(MARK(first(first(0, y0), y1)))
   A__FIRST(s(z0), cons(first(first(nil, y0), y1), z2)) -> c1(MARK(first(first(nil, y0), y1)))
   A__FIRST(s(z0), cons(first(first(s(y0), y1), y2), z2)) -> c1(MARK(first(first(s(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(cons(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(y0, y1), 0), z2)) -> c1(MARK(first(first(y0, y1), 0)))
   A__FIRST(s(z0), cons(first(first(y0, y1), nil), z2)) -> c1(MARK(first(first(y0, y1), nil)))
   A__FIRST(s(z0), cons(first(first(y0, y1), s(y2)), z2)) -> c1(MARK(first(first(y0, y1), s(y2))))
   A__FIRST(s(z0), cons(first(first(y0, y1), y2), z2)) -> c1(MARK(first(first(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(from(first(y0, y1)), y2), z2)) -> c1(MARK(first(from(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(from(y0)), y1), z2)) -> c1(MARK(first(from(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(0), y0), z2)) -> c1(MARK(first(from(0), y0)))
   A__FIRST(s(z0), cons(first(from(nil), y0), z2)) -> c1(MARK(first(from(nil), y0)))
   A__FIRST(s(z0), cons(first(from(s(y0)), y1), z2)) -> c1(MARK(first(from(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(cons(y0, y1)), y2), z2)) -> c1(MARK(first(from(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(y0), y1), z2)) -> c1(MARK(first(from(y0), y1)))
   A__FIRST(s(z0), cons(first(from(y0), 0), z2)) -> c1(MARK(first(from(y0), 0)))
   A__FIRST(s(z0), cons(first(from(y0), nil), z2)) -> c1(MARK(first(from(y0), nil)))
   A__FIRST(s(z0), cons(first(from(y0), s(y1)), z2)) -> c1(MARK(first(from(y0), s(y1))))
   A__FIRST(s(z0), cons(first(s(first(y0, y1)), y2), z2)) -> c1(MARK(first(s(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(from(y0)), y1), z2)) -> c1(MARK(first(s(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(0), y0), z2)) -> c1(MARK(first(s(0), y0)))
   A__FIRST(s(z0), cons(first(s(nil), y0), z2)) -> c1(MARK(first(s(nil), y0)))
   A__FIRST(s(z0), cons(first(s(s(y0)), y1), z2)) -> c1(MARK(first(s(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(cons(y0, y1)), y2), z2)) -> c1(MARK(first(s(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(y0), y1), z2)) -> c1(MARK(first(s(y0), y1)))
   A__FIRST(s(z0), cons(first(s(y0), 0), z2)) -> c1(MARK(first(s(y0), 0)))
   A__FIRST(s(z0), cons(first(s(y0), nil), z2)) -> c1(MARK(first(s(y0), nil)))
   A__FIRST(s(z0), cons(first(s(y0), s(y1)), z2)) -> c1(MARK(first(s(y0), s(y1))))
   A__FIRST(s(z0), cons(first(0, first(y0, y1)), z2)) -> c1(MARK(first(0, first(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, first(y0, y1)), z2)) -> c1(MARK(first(nil, first(y0, y1))))
   A__FIRST(s(z0), cons(first(0, from(y0)), z2)) -> c1(MARK(first(0, from(y0))))
   A__FIRST(s(z0), cons(first(nil, from(y0)), z2)) -> c1(MARK(first(nil, from(y0))))
   A__FIRST(s(z0), cons(first(y0, cons(y1, y2)), z2)) -> c1(MARK(first(y0, cons(y1, y2))))
   A__FIRST(s(z0), cons(first(0, cons(y0, y1)), z2)) -> c1(MARK(first(0, cons(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, cons(y0, y1)), z2)) -> c1(MARK(first(nil, cons(y0, y1))))
   MARK(first(x0, cons(0, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(MARK(x0))
   A__FROM(from(y0)) -> c3(MARK(from(y0)))
   A__FROM(s(y0)) -> c3(MARK(s(y0)))
   A__FROM(cons(y0, y1)) -> c3(MARK(cons(y0, y1)))
   A__FROM(first(y0, 0)) -> c3(MARK(first(y0, 0)))
   A__FROM(first(y0, nil)) -> c3(MARK(first(y0, nil)))
   A__FROM(first(y0, s(y1))) -> c3(MARK(first(y0, s(y1))))
   A__FROM(first(cons(y0, y1), y2)) -> c3(MARK(first(cons(y0, y1), y2)))
   A__FROM(first(0, y0)) -> c3(MARK(first(0, y0)))
   A__FROM(first(nil, y0)) -> c3(MARK(first(nil, y0)))
   A__FROM(first(y0, first(y1, first(y2, y3)))) -> c3(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FROM(first(y0, first(y1, from(y2)))) -> c3(MARK(first(y0, first(y1, from(y2)))))
   A__FROM(first(y0, first(y1, 0))) -> c3(MARK(first(y0, first(y1, 0))))
   A__FROM(first(y0, first(y1, nil))) -> c3(MARK(first(y0, first(y1, nil))))
   A__FROM(first(y0, first(y1, s(y2)))) -> c3(MARK(first(y0, first(y1, s(y2)))))
   A__FROM(first(y0, first(y1, cons(y2, y3)))) -> c3(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FROM(first(y0, first(first(y1, y2), y3))) -> c3(MARK(first(y0, first(first(y1, y2), y3))))
   A__FROM(first(y0, first(from(y1), y2))) -> c3(MARK(first(y0, first(from(y1), y2))))
   A__FROM(first(y0, first(0, y1))) -> c3(MARK(first(y0, first(0, y1))))
   A__FROM(first(y0, first(nil, y1))) -> c3(MARK(first(y0, first(nil, y1))))
   A__FROM(first(y0, first(s(y1), y2))) -> c3(MARK(first(y0, first(s(y1), y2))))
   A__FROM(first(y0, first(cons(y1, y2), y3))) -> c3(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), first(y2, y3))) -> c3(MARK(first(first(y0, y1), first(y2, y3))))
   A__FROM(first(from(y0), first(y1, y2))) -> c3(MARK(first(from(y0), first(y1, y2))))
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   MARK(cons(from(first(first(y0, y1), y2)), z1)) -> c11(MARK(from(first(first(y0, y1), y2))))
   MARK(cons(from(first(from(y0), y1)), z1)) -> c11(MARK(from(first(from(y0), y1))))
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   MARK(cons(from(first(nil, y0)), z1)) -> c11(MARK(from(first(nil, y0))))
   MARK(cons(from(first(s(y0), y1)), z1)) -> c11(MARK(from(first(s(y0), y1))))
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   MARK(cons(from(from(first(y0, y1))), z1)) -> c11(MARK(from(from(first(y0, y1)))))
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   MARK(cons(s(first(y0, s(y1))), z1)) -> c11(MARK(s(first(y0, s(y1)))))
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   MARK(cons(s(first(s(cons(y0, y1)), y2)), z1)) -> c11(MARK(s(first(s(cons(y0, y1)), y2))))
   MARK(cons(s(first(s(y0), y1)), z1)) -> c11(MARK(s(first(s(y0), y1))))
   MARK(cons(s(first(s(y0), 0)), z1)) -> c11(MARK(s(first(s(y0), 0))))
   MARK(cons(s(first(s(y0), nil)), z1)) -> c11(MARK(s(first(s(y0), nil))))
   MARK(cons(s(first(s(y0), s(y1))), z1)) -> c11(MARK(s(first(s(y0), s(y1)))))
   MARK(cons(s(first(0, first(y0, y1))), z1)) -> c11(MARK(s(first(0, first(y0, y1)))))
   MARK(cons(s(first(nil, first(y0, y1))), z1)) -> c11(MARK(s(first(nil, first(y0, y1)))))
   MARK(cons(s(first(0, from(y0))), z1)) -> c11(MARK(s(first(0, from(y0)))))
   MARK(cons(s(first(nil, from(y0))), z1)) -> c11(MARK(s(first(nil, from(y0)))))
   MARK(cons(s(first(y0, cons(y1, y2))), z1)) -> c11(MARK(s(first(y0, cons(y1, y2)))))
   MARK(cons(s(first(0, cons(y0, y1))), z1)) -> c11(MARK(s(first(0, cons(y0, y1)))))
   MARK(cons(s(first(nil, cons(y0, y1))), z1)) -> c11(MARK(s(first(nil, cons(y0, y1)))))
   MARK(cons(s(first(from(0), y0)), z1)) -> c11(MARK(s(first(from(0), y0))))
   MARK(cons(s(first(from(nil), y0)), z1)) -> c11(MARK(s(first(from(nil), y0))))
   MARK(cons(s(first(y0, cons(0, y1))), z1)) -> c11(MARK(s(first(y0, cons(0, y1)))))
   MARK(cons(s(first(y0, cons(nil, y1))), z1)) -> c11(MARK(s(first(y0, cons(nil, y1)))))
   MARK(cons(s(from(s(y0))), z1)) -> c11(MARK(s(from(s(y0)))))
   MARK(cons(s(from(cons(y0, y1))), z1)) -> c11(MARK(s(from(cons(y0, y1)))))
   MARK(cons(s(from(first(y0, y1))), z1)) -> c11(MARK(s(from(first(y0, y1)))))
   MARK(cons(s(from(first(y0, first(y1, y2)))), z1)) -> c11(MARK(s(from(first(y0, first(y1, y2))))))
   MARK(cons(s(from(first(y0, from(y1)))), z1)) -> c11(MARK(s(from(first(y0, from(y1))))))
   MARK(cons(s(from(first(y0, 0))), z1)) -> c11(MARK(s(from(first(y0, 0)))))
   MARK(cons(s(from(first(y0, nil))), z1)) -> c11(MARK(s(from(first(y0, nil)))))
   MARK(cons(s(from(first(y0, s(y1)))), z1)) -> c11(MARK(s(from(first(y0, s(y1))))))
   MARK(cons(s(from(first(y0, cons(y1, y2)))), z1)) -> c11(MARK(s(from(first(y0, cons(y1, y2))))))
   MARK(cons(s(from(first(first(y0, y1), y2))), z1)) -> c11(MARK(s(from(first(first(y0, y1), y2)))))
   MARK(cons(s(from(first(from(y0), y1))), z1)) -> c11(MARK(s(from(first(from(y0), y1)))))
   MARK(cons(s(from(first(0, y0))), z1)) -> c11(MARK(s(from(first(0, y0)))))
   MARK(cons(s(from(first(nil, y0))), z1)) -> c11(MARK(s(from(first(nil, y0)))))
   MARK(cons(s(from(first(s(y0), y1))), z1)) -> c11(MARK(s(from(first(s(y0), y1)))))
   MARK(cons(s(from(first(cons(y0, y1), y2))), z1)) -> c11(MARK(s(from(first(cons(y0, y1), y2)))))
   MARK(cons(s(from(from(y0))), z1)) -> c11(MARK(s(from(from(y0)))))
   MARK(cons(s(from(from(first(y0, y1)))), z1)) -> c11(MARK(s(from(from(first(y0, y1))))))
   MARK(cons(s(from(from(from(y0)))), z1)) -> c11(MARK(s(from(from(from(y0))))))
   MARK(cons(s(from(from(s(y0)))), z1)) -> c11(MARK(s(from(from(s(y0))))))
   MARK(cons(s(from(from(cons(y0, y1)))), z1)) -> c11(MARK(s(from(from(cons(y0, y1))))))
   MARK(cons(s(from(from(0))), z1)) -> c11(MARK(s(from(from(0)))))
   MARK(cons(s(from(from(nil))), z1)) -> c11(MARK(s(from(from(nil)))))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   MARK_1, A__FIRST_2, A__FROM_1

Compound Symbols:   c5_1, c6_1, c5_2, c6_2, c1_1, c3_1, c7_2, c7_1, c10_1, c11_1


----------------------------------------

(123) CdtForwardInstantiationProof (BOTH BOUNDS(ID, ID))
Use forward instantiation to replace MARK(first(x0, 0)) -> c5(MARK(x0)) by 
   MARK(first(first(y0, 0), 0)) -> c5(MARK(first(y0, 0)))
   MARK(first(first(y0, nil), 0)) -> c5(MARK(first(y0, nil)))
   MARK(first(first(y0, s(y1)), 0)) -> c5(MARK(first(y0, s(y1))))
   MARK(first(first(cons(y0, y1), y2), 0)) -> c5(MARK(first(cons(y0, y1), y2)))
   MARK(first(first(0, y0), 0)) -> c5(MARK(first(0, y0)))
   MARK(first(first(nil, y0), 0)) -> c5(MARK(first(nil, y0)))
   MARK(first(first(y0, first(y1, first(y2, y3))), 0)) -> c5(MARK(first(y0, first(y1, first(y2, y3)))))
   MARK(first(first(y0, first(y1, from(y2))), 0)) -> c5(MARK(first(y0, first(y1, from(y2)))))
   MARK(first(first(y0, first(y1, 0)), 0)) -> c5(MARK(first(y0, first(y1, 0))))
   MARK(first(first(y0, first(y1, nil)), 0)) -> c5(MARK(first(y0, first(y1, nil))))
   MARK(first(first(y0, first(y1, s(y2))), 0)) -> c5(MARK(first(y0, first(y1, s(y2)))))
   MARK(first(first(y0, first(y1, cons(y2, y3))), 0)) -> c5(MARK(first(y0, first(y1, cons(y2, y3)))))
   MARK(first(first(y0, first(first(y1, y2), y3)), 0)) -> c5(MARK(first(y0, first(first(y1, y2), y3))))
   MARK(first(first(y0, first(from(y1), y2)), 0)) -> c5(MARK(first(y0, first(from(y1), y2))))
   MARK(first(first(y0, first(0, y1)), 0)) -> c5(MARK(first(y0, first(0, y1))))
   MARK(first(first(y0, first(nil, y1)), 0)) -> c5(MARK(first(y0, first(nil, y1))))
   MARK(first(first(y0, first(s(y1), y2)), 0)) -> c5(MARK(first(y0, first(s(y1), y2))))
   MARK(first(first(y0, first(cons(y1, y2), y3)), 0)) -> c5(MARK(first(y0, first(cons(y1, y2), y3))))
   MARK(first(first(first(y0, y1), first(y2, y3)), 0)) -> c5(MARK(first(first(y0, y1), first(y2, y3))))
   MARK(first(first(from(y0), first(y1, y2)), 0)) -> c5(MARK(first(from(y0), first(y1, y2))))
   MARK(first(first(s(y0), first(y1, y2)), 0)) -> c5(MARK(first(s(y0), first(y1, y2))))
   MARK(first(first(y0, first(y1, y2)), 0)) -> c5(MARK(first(y0, first(y1, y2))))
   MARK(first(first(cons(y0, y1), first(y2, y3)), 0)) -> c5(MARK(first(cons(y0, y1), first(y2, y3))))
   MARK(first(first(y0, from(y1)), 0)) -> c5(MARK(first(y0, from(y1))))
   MARK(first(first(y0, from(first(y1, y2))), 0)) -> c5(MARK(first(y0, from(first(y1, y2)))))
   MARK(first(first(y0, from(from(y1))), 0)) -> c5(MARK(first(y0, from(from(y1)))))
   MARK(first(first(y0, from(0)), 0)) -> c5(MARK(first(y0, from(0))))
   MARK(first(first(y0, from(nil)), 0)) -> c5(MARK(first(y0, from(nil))))
   MARK(first(first(y0, from(s(y1))), 0)) -> c5(MARK(first(y0, from(s(y1)))))
   MARK(first(first(y0, from(cons(y1, y2))), 0)) -> c5(MARK(first(y0, from(cons(y1, y2)))))
   MARK(first(first(first(y0, y1), from(y2)), 0)) -> c5(MARK(first(first(y0, y1), from(y2))))
   MARK(first(first(from(y0), from(y1)), 0)) -> c5(MARK(first(from(y0), from(y1))))
   MARK(first(first(s(y0), from(y1)), 0)) -> c5(MARK(first(s(y0), from(y1))))
   MARK(first(first(cons(y0, y1), from(y2)), 0)) -> c5(MARK(first(cons(y0, y1), from(y2))))
   MARK(first(first(y0, cons(first(y1, y2), y3)), 0)) -> c5(MARK(first(y0, cons(first(y1, y2), y3))))
   MARK(first(first(y0, cons(from(y1), y2)), 0)) -> c5(MARK(first(y0, cons(from(y1), y2))))
   MARK(first(first(y0, cons(s(y1), y2)), 0)) -> c5(MARK(first(y0, cons(s(y1), y2))))
   MARK(first(first(y0, cons(cons(y1, y2), y3)), 0)) -> c5(MARK(first(y0, cons(cons(y1, y2), y3))))
   MARK(first(first(first(y0, y1), cons(y2, y3)), 0)) -> c5(MARK(first(first(y0, y1), cons(y2, y3))))
   MARK(first(first(from(y0), cons(y1, y2)), 0)) -> c5(MARK(first(from(y0), cons(y1, y2))))
   MARK(first(first(s(y0), cons(y1, y2)), 0)) -> c5(MARK(first(s(y0), cons(y1, y2))))
   MARK(first(first(cons(y0, y1), cons(y2, y3)), 0)) -> c5(MARK(first(cons(y0, y1), cons(y2, y3))))
   MARK(first(first(first(y0, first(y1, y2)), y3), 0)) -> c5(MARK(first(first(y0, first(y1, y2)), y3)))
   MARK(first(first(first(y0, from(y1)), y2), 0)) -> c5(MARK(first(first(y0, from(y1)), y2)))
   MARK(first(first(first(y0, 0), y1), 0)) -> c5(MARK(first(first(y0, 0), y1)))
   MARK(first(first(first(y0, nil), y1), 0)) -> c5(MARK(first(first(y0, nil), y1)))
   MARK(first(first(first(y0, s(y1)), y2), 0)) -> c5(MARK(first(first(y0, s(y1)), y2)))
   MARK(first(first(first(y0, cons(y1, y2)), y3), 0)) -> c5(MARK(first(first(y0, cons(y1, y2)), y3)))
   MARK(first(first(first(first(y0, y1), y2), y3), 0)) -> c5(MARK(first(first(first(y0, y1), y2), y3)))
   MARK(first(first(first(from(y0), y1), y2), 0)) -> c5(MARK(first(first(from(y0), y1), y2)))
   MARK(first(first(first(0, y0), y1), 0)) -> c5(MARK(first(first(0, y0), y1)))
   MARK(first(first(first(nil, y0), y1), 0)) -> c5(MARK(first(first(nil, y0), y1)))
   MARK(first(first(first(s(y0), y1), y2), 0)) -> c5(MARK(first(first(s(y0), y1), y2)))
   MARK(first(first(first(cons(y0, y1), y2), y3), 0)) -> c5(MARK(first(first(cons(y0, y1), y2), y3)))
   MARK(first(first(first(y0, y1), 0), 0)) -> c5(MARK(first(first(y0, y1), 0)))
   MARK(first(first(first(y0, y1), nil), 0)) -> c5(MARK(first(first(y0, y1), nil)))
   MARK(first(first(first(y0, y1), s(y2)), 0)) -> c5(MARK(first(first(y0, y1), s(y2))))
   MARK(first(first(first(y0, y1), y2), 0)) -> c5(MARK(first(first(y0, y1), y2)))
   MARK(first(first(from(first(y0, y1)), y2), 0)) -> c5(MARK(first(from(first(y0, y1)), y2)))
   MARK(first(first(from(from(y0)), y1), 0)) -> c5(MARK(first(from(from(y0)), y1)))
   MARK(first(first(from(s(y0)), y1), 0)) -> c5(MARK(first(from(s(y0)), y1)))
   MARK(first(first(from(cons(y0, y1)), y2), 0)) -> c5(MARK(first(from(cons(y0, y1)), y2)))
   MARK(first(first(from(y0), y1), 0)) -> c5(MARK(first(from(y0), y1)))
   MARK(first(first(from(y0), 0), 0)) -> c5(MARK(first(from(y0), 0)))
   MARK(first(first(from(y0), nil), 0)) -> c5(MARK(first(from(y0), nil)))
   MARK(first(first(from(y0), s(y1)), 0)) -> c5(MARK(first(from(y0), s(y1))))
   MARK(first(first(s(first(y0, y1)), y2), 0)) -> c5(MARK(first(s(first(y0, y1)), y2)))
   MARK(first(first(s(from(y0)), y1), 0)) -> c5(MARK(first(s(from(y0)), y1)))
   MARK(first(first(s(s(y0)), y1), 0)) -> c5(MARK(first(s(s(y0)), y1)))
   MARK(first(first(s(cons(y0, y1)), y2), 0)) -> c5(MARK(first(s(cons(y0, y1)), y2)))
   MARK(first(first(s(y0), y1), 0)) -> c5(MARK(first(s(y0), y1)))
   MARK(first(first(s(y0), 0), 0)) -> c5(MARK(first(s(y0), 0)))
   MARK(first(first(s(y0), nil), 0)) -> c5(MARK(first(s(y0), nil)))
   MARK(first(first(s(y0), s(y1)), 0)) -> c5(MARK(first(s(y0), s(y1))))
   MARK(first(first(0, first(y0, y1)), 0)) -> c5(MARK(first(0, first(y0, y1))))
   MARK(first(first(nil, first(y0, y1)), 0)) -> c5(MARK(first(nil, first(y0, y1))))
   MARK(first(first(0, from(y0)), 0)) -> c5(MARK(first(0, from(y0))))
   MARK(first(first(nil, from(y0)), 0)) -> c5(MARK(first(nil, from(y0))))
   MARK(first(first(y0, cons(y1, y2)), 0)) -> c5(MARK(first(y0, cons(y1, y2))))
   MARK(first(first(0, cons(y0, y1)), 0)) -> c5(MARK(first(0, cons(y0, y1))))
   MARK(first(first(nil, cons(y0, y1)), 0)) -> c5(MARK(first(nil, cons(y0, y1))))
   MARK(first(first(from(0), y0), 0)) -> c5(MARK(first(from(0), y0)))
   MARK(first(first(from(nil), y0), 0)) -> c5(MARK(first(from(nil), y0)))
   MARK(first(first(s(0), y0), 0)) -> c5(MARK(first(s(0), y0)))
   MARK(first(first(s(nil), y0), 0)) -> c5(MARK(first(s(nil), y0)))
   MARK(first(first(y0, cons(0, y1)), 0)) -> c5(MARK(first(y0, cons(0, y1))))
   MARK(first(first(y0, cons(nil, y1)), 0)) -> c5(MARK(first(y0, cons(nil, y1))))
   MARK(first(from(s(y0)), 0)) -> c5(MARK(from(s(y0))))
   MARK(first(from(cons(y0, y1)), 0)) -> c5(MARK(from(cons(y0, y1))))
   MARK(first(from(first(y0, y1)), 0)) -> c5(MARK(from(first(y0, y1))))
   MARK(first(from(first(y0, first(y1, y2))), 0)) -> c5(MARK(from(first(y0, first(y1, y2)))))
   MARK(first(from(first(y0, from(y1))), 0)) -> c5(MARK(from(first(y0, from(y1)))))
   MARK(first(from(first(y0, 0)), 0)) -> c5(MARK(from(first(y0, 0))))
   MARK(first(from(first(y0, nil)), 0)) -> c5(MARK(from(first(y0, nil))))
   MARK(first(from(first(y0, s(y1))), 0)) -> c5(MARK(from(first(y0, s(y1)))))
   MARK(first(from(first(y0, cons(y1, y2))), 0)) -> c5(MARK(from(first(y0, cons(y1, y2)))))
   MARK(first(from(first(first(y0, y1), y2)), 0)) -> c5(MARK(from(first(first(y0, y1), y2))))
   MARK(first(from(first(from(y0), y1)), 0)) -> c5(MARK(from(first(from(y0), y1))))
   MARK(first(from(first(0, y0)), 0)) -> c5(MARK(from(first(0, y0))))
   MARK(first(from(first(nil, y0)), 0)) -> c5(MARK(from(first(nil, y0))))
   MARK(first(from(first(s(y0), y1)), 0)) -> c5(MARK(from(first(s(y0), y1))))
   MARK(first(from(first(cons(y0, y1), y2)), 0)) -> c5(MARK(from(first(cons(y0, y1), y2))))
   MARK(first(from(from(y0)), 0)) -> c5(MARK(from(from(y0))))
   MARK(first(from(from(first(y0, y1))), 0)) -> c5(MARK(from(from(first(y0, y1)))))
   MARK(first(from(from(from(y0))), 0)) -> c5(MARK(from(from(from(y0)))))
   MARK(first(from(from(s(y0))), 0)) -> c5(MARK(from(from(s(y0)))))
   MARK(first(from(from(cons(y0, y1))), 0)) -> c5(MARK(from(from(cons(y0, y1)))))
   MARK(first(from(from(0)), 0)) -> c5(MARK(from(from(0))))
   MARK(first(from(from(nil)), 0)) -> c5(MARK(from(from(nil))))
   MARK(first(s(s(y0)), 0)) -> c5(MARK(s(s(y0))))
   MARK(first(s(cons(y0, y1)), 0)) -> c5(MARK(s(cons(y0, y1))))
   MARK(first(s(first(y0, 0)), 0)) -> c5(MARK(s(first(y0, 0))))
   MARK(first(s(first(y0, nil)), 0)) -> c5(MARK(s(first(y0, nil))))
   MARK(first(s(first(y0, s(y1))), 0)) -> c5(MARK(s(first(y0, s(y1)))))
   MARK(first(s(first(cons(y0, y1), y2)), 0)) -> c5(MARK(s(first(cons(y0, y1), y2))))
   MARK(first(s(first(0, y0)), 0)) -> c5(MARK(s(first(0, y0))))
   MARK(first(s(first(nil, y0)), 0)) -> c5(MARK(s(first(nil, y0))))
   MARK(first(s(first(y0, first(y1, first(y2, y3)))), 0)) -> c5(MARK(s(first(y0, first(y1, first(y2, y3))))))
   MARK(first(s(first(y0, first(y1, from(y2)))), 0)) -> c5(MARK(s(first(y0, first(y1, from(y2))))))
   MARK(first(s(first(y0, first(y1, 0))), 0)) -> c5(MARK(s(first(y0, first(y1, 0)))))
   MARK(first(s(first(y0, first(y1, nil))), 0)) -> c5(MARK(s(first(y0, first(y1, nil)))))
   MARK(first(s(first(y0, first(y1, s(y2)))), 0)) -> c5(MARK(s(first(y0, first(y1, s(y2))))))
   MARK(first(s(first(y0, first(y1, cons(y2, y3)))), 0)) -> c5(MARK(s(first(y0, first(y1, cons(y2, y3))))))
   MARK(first(s(first(y0, first(first(y1, y2), y3))), 0)) -> c5(MARK(s(first(y0, first(first(y1, y2), y3)))))
   MARK(first(s(first(y0, first(from(y1), y2))), 0)) -> c5(MARK(s(first(y0, first(from(y1), y2)))))
   MARK(first(s(first(y0, first(0, y1))), 0)) -> c5(MARK(s(first(y0, first(0, y1)))))
   MARK(first(s(first(y0, first(nil, y1))), 0)) -> c5(MARK(s(first(y0, first(nil, y1)))))
   MARK(first(s(first(y0, first(s(y1), y2))), 0)) -> c5(MARK(s(first(y0, first(s(y1), y2)))))
   MARK(first(s(first(y0, first(cons(y1, y2), y3))), 0)) -> c5(MARK(s(first(y0, first(cons(y1, y2), y3)))))
   MARK(first(s(first(first(y0, y1), first(y2, y3))), 0)) -> c5(MARK(s(first(first(y0, y1), first(y2, y3)))))
   MARK(first(s(first(from(y0), first(y1, y2))), 0)) -> c5(MARK(s(first(from(y0), first(y1, y2)))))
   MARK(first(s(first(s(y0), first(y1, y2))), 0)) -> c5(MARK(s(first(s(y0), first(y1, y2)))))
   MARK(first(s(first(y0, first(y1, y2))), 0)) -> c5(MARK(s(first(y0, first(y1, y2)))))
   MARK(first(s(first(cons(y0, y1), first(y2, y3))), 0)) -> c5(MARK(s(first(cons(y0, y1), first(y2, y3)))))
   MARK(first(s(first(y0, from(y1))), 0)) -> c5(MARK(s(first(y0, from(y1)))))
   MARK(first(s(first(y0, from(first(y1, y2)))), 0)) -> c5(MARK(s(first(y0, from(first(y1, y2))))))
   MARK(first(s(first(y0, from(from(y1)))), 0)) -> c5(MARK(s(first(y0, from(from(y1))))))
   MARK(first(s(first(y0, from(0))), 0)) -> c5(MARK(s(first(y0, from(0)))))
   MARK(first(s(first(y0, from(nil))), 0)) -> c5(MARK(s(first(y0, from(nil)))))
   MARK(first(s(first(y0, from(s(y1)))), 0)) -> c5(MARK(s(first(y0, from(s(y1))))))
   MARK(first(s(first(y0, from(cons(y1, y2)))), 0)) -> c5(MARK(s(first(y0, from(cons(y1, y2))))))
   MARK(first(s(first(first(y0, y1), from(y2))), 0)) -> c5(MARK(s(first(first(y0, y1), from(y2)))))
   MARK(first(s(first(from(y0), from(y1))), 0)) -> c5(MARK(s(first(from(y0), from(y1)))))
   MARK(first(s(first(s(y0), from(y1))), 0)) -> c5(MARK(s(first(s(y0), from(y1)))))
   MARK(first(s(first(cons(y0, y1), from(y2))), 0)) -> c5(MARK(s(first(cons(y0, y1), from(y2)))))
   MARK(first(s(first(y0, cons(first(y1, y2), y3))), 0)) -> c5(MARK(s(first(y0, cons(first(y1, y2), y3)))))
   MARK(first(s(first(y0, cons(from(y1), y2))), 0)) -> c5(MARK(s(first(y0, cons(from(y1), y2)))))
   MARK(first(s(first(y0, cons(s(y1), y2))), 0)) -> c5(MARK(s(first(y0, cons(s(y1), y2)))))
   MARK(first(s(first(y0, cons(cons(y1, y2), y3))), 0)) -> c5(MARK(s(first(y0, cons(cons(y1, y2), y3)))))
   MARK(first(s(first(first(y0, y1), cons(y2, y3))), 0)) -> c5(MARK(s(first(first(y0, y1), cons(y2, y3)))))
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   MARK(first(cons(from(first(from(y0), y1)), y2), 0)) -> c5(MARK(cons(from(first(from(y0), y1)), y2)))
   MARK(first(cons(from(first(0, y0)), y1), 0)) -> c5(MARK(cons(from(first(0, y0)), y1)))
   MARK(first(cons(from(first(nil, y0)), y1), 0)) -> c5(MARK(cons(from(first(nil, y0)), y1)))
   MARK(first(cons(from(first(s(y0), y1)), y2), 0)) -> c5(MARK(cons(from(first(s(y0), y1)), y2)))
   MARK(first(cons(from(first(cons(y0, y1), y2)), y3), 0)) -> c5(MARK(cons(from(first(cons(y0, y1), y2)), y3)))
   MARK(first(cons(from(from(y0)), y1), 0)) -> c5(MARK(cons(from(from(y0)), y1)))
   MARK(first(cons(from(from(first(y0, y1))), y2), 0)) -> c5(MARK(cons(from(from(first(y0, y1))), y2)))
   MARK(first(cons(from(from(from(y0))), y1), 0)) -> c5(MARK(cons(from(from(from(y0))), y1)))
   MARK(first(cons(from(from(s(y0))), y1), 0)) -> c5(MARK(cons(from(from(s(y0))), y1)))
   MARK(first(cons(from(from(cons(y0, y1))), y2), 0)) -> c5(MARK(cons(from(from(cons(y0, y1))), y2)))
   MARK(first(cons(from(from(0)), y0), 0)) -> c5(MARK(cons(from(from(0)), y0)))
   MARK(first(cons(from(from(nil)), y0), 0)) -> c5(MARK(cons(from(from(nil)), y0)))
   MARK(first(cons(s(s(y0)), y1), 0)) -> c5(MARK(cons(s(s(y0)), y1)))
   MARK(first(cons(s(cons(y0, y1)), y2), 0)) -> c5(MARK(cons(s(cons(y0, y1)), y2)))
   MARK(first(cons(s(first(y0, 0)), y1), 0)) -> c5(MARK(cons(s(first(y0, 0)), y1)))
   MARK(first(cons(s(first(y0, nil)), y1), 0)) -> c5(MARK(cons(s(first(y0, nil)), y1)))
   MARK(first(cons(s(first(y0, s(y1))), y2), 0)) -> c5(MARK(cons(s(first(y0, s(y1))), y2)))
   MARK(first(cons(s(first(cons(y0, y1), y2)), y3), 0)) -> c5(MARK(cons(s(first(cons(y0, y1), y2)), y3)))
   MARK(first(cons(s(first(0, y0)), y1), 0)) -> c5(MARK(cons(s(first(0, y0)), y1)))
   MARK(first(cons(s(first(nil, y0)), y1), 0)) -> c5(MARK(cons(s(first(nil, y0)), y1)))
   MARK(first(cons(s(first(y0, first(y1, first(y2, y3)))), y4), 0)) -> c5(MARK(cons(s(first(y0, first(y1, first(y2, y3)))), y4)))
   MARK(first(cons(s(first(y0, first(y1, from(y2)))), y3), 0)) -> c5(MARK(cons(s(first(y0, first(y1, from(y2)))), y3)))
   MARK(first(cons(s(first(y0, first(y1, 0))), y2), 0)) -> c5(MARK(cons(s(first(y0, first(y1, 0))), y2)))
   MARK(first(cons(s(first(y0, first(y1, nil))), y2), 0)) -> c5(MARK(cons(s(first(y0, first(y1, nil))), y2)))
   MARK(first(cons(s(first(y0, first(y1, s(y2)))), y3), 0)) -> c5(MARK(cons(s(first(y0, first(y1, s(y2)))), y3)))
   MARK(first(cons(s(first(y0, first(y1, cons(y2, y3)))), y4), 0)) -> c5(MARK(cons(s(first(y0, first(y1, cons(y2, y3)))), y4)))
   MARK(first(cons(s(first(y0, first(first(y1, y2), y3))), y4), 0)) -> c5(MARK(cons(s(first(y0, first(first(y1, y2), y3))), y4)))
   MARK(first(cons(s(first(y0, first(from(y1), y2))), y3), 0)) -> c5(MARK(cons(s(first(y0, first(from(y1), y2))), y3)))
   MARK(first(cons(s(first(y0, first(0, y1))), y2), 0)) -> c5(MARK(cons(s(first(y0, first(0, y1))), y2)))
   MARK(first(cons(s(first(y0, first(nil, y1))), y2), 0)) -> c5(MARK(cons(s(first(y0, first(nil, y1))), y2)))
   MARK(first(cons(s(first(y0, first(s(y1), y2))), y3), 0)) -> c5(MARK(cons(s(first(y0, first(s(y1), y2))), y3)))
   MARK(first(cons(s(first(y0, first(cons(y1, y2), y3))), y4), 0)) -> c5(MARK(cons(s(first(y0, first(cons(y1, y2), y3))), y4)))
   MARK(first(cons(s(first(first(y0, y1), first(y2, y3))), y4), 0)) -> c5(MARK(cons(s(first(first(y0, y1), first(y2, y3))), y4)))
   MARK(first(cons(s(first(from(y0), first(y1, y2))), y3), 0)) -> c5(MARK(cons(s(first(from(y0), first(y1, y2))), y3)))
   MARK(first(cons(s(first(s(y0), first(y1, y2))), y3), 0)) -> c5(MARK(cons(s(first(s(y0), first(y1, y2))), y3)))
   MARK(first(cons(s(first(y0, first(y1, y2))), y3), 0)) -> c5(MARK(cons(s(first(y0, first(y1, y2))), y3)))
   MARK(first(cons(s(first(cons(y0, y1), first(y2, y3))), y4), 0)) -> c5(MARK(cons(s(first(cons(y0, y1), first(y2, y3))), y4)))
   MARK(first(cons(s(first(y0, from(y1))), y2), 0)) -> c5(MARK(cons(s(first(y0, from(y1))), y2)))
   MARK(first(cons(s(first(y0, from(first(y1, y2)))), y3), 0)) -> c5(MARK(cons(s(first(y0, from(first(y1, y2)))), y3)))
   MARK(first(cons(s(first(y0, from(from(y1)))), y2), 0)) -> c5(MARK(cons(s(first(y0, from(from(y1)))), y2)))
   MARK(first(cons(s(first(y0, from(0))), y1), 0)) -> c5(MARK(cons(s(first(y0, from(0))), y1)))
   MARK(first(cons(s(first(y0, from(nil))), y1), 0)) -> c5(MARK(cons(s(first(y0, from(nil))), y1)))
   MARK(first(cons(s(first(y0, from(s(y1)))), y2), 0)) -> c5(MARK(cons(s(first(y0, from(s(y1)))), y2)))
   MARK(first(cons(s(first(y0, from(cons(y1, y2)))), y3), 0)) -> c5(MARK(cons(s(first(y0, from(cons(y1, y2)))), y3)))
   MARK(first(cons(s(first(first(y0, y1), from(y2))), y3), 0)) -> c5(MARK(cons(s(first(first(y0, y1), from(y2))), y3)))
   MARK(first(cons(s(first(from(y0), from(y1))), y2), 0)) -> c5(MARK(cons(s(first(from(y0), from(y1))), y2)))
   MARK(first(cons(s(first(s(y0), from(y1))), y2), 0)) -> c5(MARK(cons(s(first(s(y0), from(y1))), y2)))
   MARK(first(cons(s(first(cons(y0, y1), from(y2))), y3), 0)) -> c5(MARK(cons(s(first(cons(y0, y1), from(y2))), y3)))
   MARK(first(cons(s(first(y0, cons(first(y1, y2), y3))), y4), 0)) -> c5(MARK(cons(s(first(y0, cons(first(y1, y2), y3))), y4)))
   MARK(first(cons(s(first(y0, cons(from(y1), y2))), y3), 0)) -> c5(MARK(cons(s(first(y0, cons(from(y1), y2))), y3)))
   MARK(first(cons(s(first(y0, cons(s(y1), y2))), y3), 0)) -> c5(MARK(cons(s(first(y0, cons(s(y1), y2))), y3)))
   MARK(first(cons(s(first(y0, cons(cons(y1, y2), y3))), y4), 0)) -> c5(MARK(cons(s(first(y0, cons(cons(y1, y2), y3))), y4)))
   MARK(first(cons(s(first(first(y0, y1), cons(y2, y3))), y4), 0)) -> c5(MARK(cons(s(first(first(y0, y1), cons(y2, y3))), y4)))
   MARK(first(cons(s(first(from(y0), cons(y1, y2))), y3), 0)) -> c5(MARK(cons(s(first(from(y0), cons(y1, y2))), y3)))
   MARK(first(cons(s(first(s(y0), cons(y1, y2))), y3), 0)) -> c5(MARK(cons(s(first(s(y0), cons(y1, y2))), y3)))
   MARK(first(cons(s(first(cons(y0, y1), cons(y2, y3))), y4), 0)) -> c5(MARK(cons(s(first(cons(y0, y1), cons(y2, y3))), y4)))
   MARK(first(cons(s(first(first(y0, first(y1, y2)), y3)), y4), 0)) -> c5(MARK(cons(s(first(first(y0, first(y1, y2)), y3)), y4)))
   MARK(first(cons(s(first(first(y0, from(y1)), y2)), y3), 0)) -> c5(MARK(cons(s(first(first(y0, from(y1)), y2)), y3)))
   MARK(first(cons(s(first(first(y0, 0), y1)), y2), 0)) -> c5(MARK(cons(s(first(first(y0, 0), y1)), y2)))
   MARK(first(cons(s(first(first(y0, nil), y1)), y2), 0)) -> c5(MARK(cons(s(first(first(y0, nil), y1)), y2)))
   MARK(first(cons(s(first(first(y0, s(y1)), y2)), y3), 0)) -> c5(MARK(cons(s(first(first(y0, s(y1)), y2)), y3)))
   MARK(first(cons(s(first(first(y0, cons(y1, y2)), y3)), y4), 0)) -> c5(MARK(cons(s(first(first(y0, cons(y1, y2)), y3)), y4)))
   MARK(first(cons(s(first(first(first(y0, y1), y2), y3)), y4), 0)) -> c5(MARK(cons(s(first(first(first(y0, y1), y2), y3)), y4)))
   MARK(first(cons(s(first(first(from(y0), y1), y2)), y3), 0)) -> c5(MARK(cons(s(first(first(from(y0), y1), y2)), y3)))
   MARK(first(cons(s(first(first(0, y0), y1)), y2), 0)) -> c5(MARK(cons(s(first(first(0, y0), y1)), y2)))
   MARK(first(cons(s(first(first(nil, y0), y1)), y2), 0)) -> c5(MARK(cons(s(first(first(nil, y0), y1)), y2)))
   MARK(first(cons(s(first(first(s(y0), y1), y2)), y3), 0)) -> c5(MARK(cons(s(first(first(s(y0), y1), y2)), y3)))
   MARK(first(cons(s(first(first(cons(y0, y1), y2), y3)), y4), 0)) -> c5(MARK(cons(s(first(first(cons(y0, y1), y2), y3)), y4)))
   MARK(first(cons(s(first(first(y0, y1), 0)), y2), 0)) -> c5(MARK(cons(s(first(first(y0, y1), 0)), y2)))
   MARK(first(cons(s(first(first(y0, y1), nil)), y2), 0)) -> c5(MARK(cons(s(first(first(y0, y1), nil)), y2)))
   MARK(first(cons(s(first(first(y0, y1), s(y2))), y3), 0)) -> c5(MARK(cons(s(first(first(y0, y1), s(y2))), y3)))
   MARK(first(cons(s(first(first(y0, y1), y2)), y3), 0)) -> c5(MARK(cons(s(first(first(y0, y1), y2)), y3)))
   MARK(first(cons(s(first(from(first(y0, y1)), y2)), y3), 0)) -> c5(MARK(cons(s(first(from(first(y0, y1)), y2)), y3)))
   MARK(first(cons(s(first(from(from(y0)), y1)), y2), 0)) -> c5(MARK(cons(s(first(from(from(y0)), y1)), y2)))
   MARK(first(cons(s(first(from(s(y0)), y1)), y2), 0)) -> c5(MARK(cons(s(first(from(s(y0)), y1)), y2)))
   MARK(first(cons(s(first(from(cons(y0, y1)), y2)), y3), 0)) -> c5(MARK(cons(s(first(from(cons(y0, y1)), y2)), y3)))
   MARK(first(cons(s(first(from(y0), y1)), y2), 0)) -> c5(MARK(cons(s(first(from(y0), y1)), y2)))
   MARK(first(cons(s(first(from(y0), 0)), y1), 0)) -> c5(MARK(cons(s(first(from(y0), 0)), y1)))
   MARK(first(cons(s(first(from(y0), nil)), y1), 0)) -> c5(MARK(cons(s(first(from(y0), nil)), y1)))
   MARK(first(cons(s(first(from(y0), s(y1))), y2), 0)) -> c5(MARK(cons(s(first(from(y0), s(y1))), y2)))
   MARK(first(cons(s(first(s(first(y0, y1)), y2)), y3), 0)) -> c5(MARK(cons(s(first(s(first(y0, y1)), y2)), y3)))
   MARK(first(cons(s(first(s(from(y0)), y1)), y2), 0)) -> c5(MARK(cons(s(first(s(from(y0)), y1)), y2)))
   MARK(first(cons(s(first(s(0), y0)), y1), 0)) -> c5(MARK(cons(s(first(s(0), y0)), y1)))
   MARK(first(cons(s(first(s(nil), y0)), y1), 0)) -> c5(MARK(cons(s(first(s(nil), y0)), y1)))
   MARK(first(cons(s(first(s(s(y0)), y1)), y2), 0)) -> c5(MARK(cons(s(first(s(s(y0)), y1)), y2)))
   MARK(first(cons(s(first(s(cons(y0, y1)), y2)), y3), 0)) -> c5(MARK(cons(s(first(s(cons(y0, y1)), y2)), y3)))
   MARK(first(cons(s(first(s(y0), y1)), y2), 0)) -> c5(MARK(cons(s(first(s(y0), y1)), y2)))
   MARK(first(cons(s(first(s(y0), 0)), y1), 0)) -> c5(MARK(cons(s(first(s(y0), 0)), y1)))
   MARK(first(cons(s(first(s(y0), nil)), y1), 0)) -> c5(MARK(cons(s(first(s(y0), nil)), y1)))
   MARK(first(cons(s(first(s(y0), s(y1))), y2), 0)) -> c5(MARK(cons(s(first(s(y0), s(y1))), y2)))
   MARK(first(cons(s(first(0, first(y0, y1))), y2), 0)) -> c5(MARK(cons(s(first(0, first(y0, y1))), y2)))
   MARK(first(cons(s(first(nil, first(y0, y1))), y2), 0)) -> c5(MARK(cons(s(first(nil, first(y0, y1))), y2)))
   MARK(first(cons(s(first(0, from(y0))), y1), 0)) -> c5(MARK(cons(s(first(0, from(y0))), y1)))
   MARK(first(cons(s(first(nil, from(y0))), y1), 0)) -> c5(MARK(cons(s(first(nil, from(y0))), y1)))
   MARK(first(cons(s(first(y0, cons(y1, y2))), y3), 0)) -> c5(MARK(cons(s(first(y0, cons(y1, y2))), y3)))
   MARK(first(cons(s(first(0, cons(y0, y1))), y2), 0)) -> c5(MARK(cons(s(first(0, cons(y0, y1))), y2)))
   MARK(first(cons(s(first(nil, cons(y0, y1))), y2), 0)) -> c5(MARK(cons(s(first(nil, cons(y0, y1))), y2)))
   MARK(first(cons(s(first(from(0), y0)), y1), 0)) -> c5(MARK(cons(s(first(from(0), y0)), y1)))
   MARK(first(cons(s(first(from(nil), y0)), y1), 0)) -> c5(MARK(cons(s(first(from(nil), y0)), y1)))
   MARK(first(cons(s(first(y0, cons(0, y1))), y2), 0)) -> c5(MARK(cons(s(first(y0, cons(0, y1))), y2)))
   MARK(first(cons(s(first(y0, cons(nil, y1))), y2), 0)) -> c5(MARK(cons(s(first(y0, cons(nil, y1))), y2)))
   MARK(first(cons(s(from(s(y0))), y1), 0)) -> c5(MARK(cons(s(from(s(y0))), y1)))
   MARK(first(cons(s(from(cons(y0, y1))), y2), 0)) -> c5(MARK(cons(s(from(cons(y0, y1))), y2)))
   MARK(first(cons(s(from(first(y0, y1))), y2), 0)) -> c5(MARK(cons(s(from(first(y0, y1))), y2)))
   MARK(first(cons(s(from(first(y0, first(y1, y2)))), y3), 0)) -> c5(MARK(cons(s(from(first(y0, first(y1, y2)))), y3)))
   MARK(first(cons(s(from(first(y0, from(y1)))), y2), 0)) -> c5(MARK(cons(s(from(first(y0, from(y1)))), y2)))
   MARK(first(cons(s(from(first(y0, 0))), y1), 0)) -> c5(MARK(cons(s(from(first(y0, 0))), y1)))
   MARK(first(cons(s(from(first(y0, nil))), y1), 0)) -> c5(MARK(cons(s(from(first(y0, nil))), y1)))
   MARK(first(cons(s(from(first(y0, s(y1)))), y2), 0)) -> c5(MARK(cons(s(from(first(y0, s(y1)))), y2)))
   MARK(first(cons(s(from(first(y0, cons(y1, y2)))), y3), 0)) -> c5(MARK(cons(s(from(first(y0, cons(y1, y2)))), y3)))
   MARK(first(cons(s(from(first(first(y0, y1), y2))), y3), 0)) -> c5(MARK(cons(s(from(first(first(y0, y1), y2))), y3)))
   MARK(first(cons(s(from(first(from(y0), y1))), y2), 0)) -> c5(MARK(cons(s(from(first(from(y0), y1))), y2)))
   MARK(first(cons(s(from(first(0, y0))), y1), 0)) -> c5(MARK(cons(s(from(first(0, y0))), y1)))
   MARK(first(cons(s(from(first(nil, y0))), y1), 0)) -> c5(MARK(cons(s(from(first(nil, y0))), y1)))
   MARK(first(cons(s(from(first(s(y0), y1))), y2), 0)) -> c5(MARK(cons(s(from(first(s(y0), y1))), y2)))
   MARK(first(cons(s(from(first(cons(y0, y1), y2))), y3), 0)) -> c5(MARK(cons(s(from(first(cons(y0, y1), y2))), y3)))
   MARK(first(cons(s(from(from(y0))), y1), 0)) -> c5(MARK(cons(s(from(from(y0))), y1)))
   MARK(first(cons(s(from(from(first(y0, y1)))), y2), 0)) -> c5(MARK(cons(s(from(from(first(y0, y1)))), y2)))
   MARK(first(cons(s(from(from(from(y0)))), y1), 0)) -> c5(MARK(cons(s(from(from(from(y0)))), y1)))
   MARK(first(cons(s(from(from(s(y0)))), y1), 0)) -> c5(MARK(cons(s(from(from(s(y0)))), y1)))
   MARK(first(cons(s(from(from(cons(y0, y1)))), y2), 0)) -> c5(MARK(cons(s(from(from(cons(y0, y1)))), y2)))
   MARK(first(cons(s(from(from(0))), y0), 0)) -> c5(MARK(cons(s(from(from(0))), y0)))
   MARK(first(cons(s(from(from(nil))), y0), 0)) -> c5(MARK(cons(s(from(from(nil))), y0)))

----------------------------------------

(124)
Obligation:
Complexity Dependency Tuples Problem

Rules:
   a__first(0, z0) -> nil
   a__first(s(z0), cons(z1, z2)) -> cons(mark(z1), first(z0, z2))
   a__first(z0, z1) -> first(z0, z1)
   a__from(z0) -> cons(mark(z0), from(s(z0)))
   a__from(z0) -> from(z0)
   mark(first(z0, z1)) -> a__first(mark(z0), mark(z1))
   mark(from(z0)) -> a__from(mark(z0))
   mark(0) -> 0
   mark(nil) -> nil
   mark(s(z0)) -> s(mark(z0))
   mark(cons(z0, z1)) -> cons(mark(z0), z1)
Tuples:
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
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   MARK(first(cons(s(first(s(y0), s(y1))), y2), 0)) -> c5(MARK(cons(s(first(s(y0), s(y1))), y2)))
   MARK(first(cons(s(first(0, first(y0, y1))), y2), 0)) -> c5(MARK(cons(s(first(0, first(y0, y1))), y2)))
   MARK(first(cons(s(first(nil, first(y0, y1))), y2), 0)) -> c5(MARK(cons(s(first(nil, first(y0, y1))), y2)))
   MARK(first(cons(s(first(0, from(y0))), y1), 0)) -> c5(MARK(cons(s(first(0, from(y0))), y1)))
   MARK(first(cons(s(first(nil, from(y0))), y1), 0)) -> c5(MARK(cons(s(first(nil, from(y0))), y1)))
   MARK(first(cons(s(first(y0, cons(y1, y2))), y3), 0)) -> c5(MARK(cons(s(first(y0, cons(y1, y2))), y3)))
   MARK(first(cons(s(first(0, cons(y0, y1))), y2), 0)) -> c5(MARK(cons(s(first(0, cons(y0, y1))), y2)))
   MARK(first(cons(s(first(nil, cons(y0, y1))), y2), 0)) -> c5(MARK(cons(s(first(nil, cons(y0, y1))), y2)))
   MARK(first(cons(s(first(from(0), y0)), y1), 0)) -> c5(MARK(cons(s(first(from(0), y0)), y1)))
   MARK(first(cons(s(first(from(nil), y0)), y1), 0)) -> c5(MARK(cons(s(first(from(nil), y0)), y1)))
   MARK(first(cons(s(first(y0, cons(0, y1))), y2), 0)) -> c5(MARK(cons(s(first(y0, cons(0, y1))), y2)))
   MARK(first(cons(s(first(y0, cons(nil, y1))), y2), 0)) -> c5(MARK(cons(s(first(y0, cons(nil, y1))), y2)))
   MARK(first(cons(s(from(s(y0))), y1), 0)) -> c5(MARK(cons(s(from(s(y0))), y1)))
   MARK(first(cons(s(from(cons(y0, y1))), y2), 0)) -> c5(MARK(cons(s(from(cons(y0, y1))), y2)))
   MARK(first(cons(s(from(first(y0, y1))), y2), 0)) -> c5(MARK(cons(s(from(first(y0, y1))), y2)))
   MARK(first(cons(s(from(first(y0, first(y1, y2)))), y3), 0)) -> c5(MARK(cons(s(from(first(y0, first(y1, y2)))), y3)))
   MARK(first(cons(s(from(first(y0, from(y1)))), y2), 0)) -> c5(MARK(cons(s(from(first(y0, from(y1)))), y2)))
   MARK(first(cons(s(from(first(y0, 0))), y1), 0)) -> c5(MARK(cons(s(from(first(y0, 0))), y1)))
   MARK(first(cons(s(from(first(y0, nil))), y1), 0)) -> c5(MARK(cons(s(from(first(y0, nil))), y1)))
   MARK(first(cons(s(from(first(y0, s(y1)))), y2), 0)) -> c5(MARK(cons(s(from(first(y0, s(y1)))), y2)))
   MARK(first(cons(s(from(first(y0, cons(y1, y2)))), y3), 0)) -> c5(MARK(cons(s(from(first(y0, cons(y1, y2)))), y3)))
   MARK(first(cons(s(from(first(first(y0, y1), y2))), y3), 0)) -> c5(MARK(cons(s(from(first(first(y0, y1), y2))), y3)))
   MARK(first(cons(s(from(first(from(y0), y1))), y2), 0)) -> c5(MARK(cons(s(from(first(from(y0), y1))), y2)))
   MARK(first(cons(s(from(first(0, y0))), y1), 0)) -> c5(MARK(cons(s(from(first(0, y0))), y1)))
   MARK(first(cons(s(from(first(nil, y0))), y1), 0)) -> c5(MARK(cons(s(from(first(nil, y0))), y1)))
   MARK(first(cons(s(from(first(s(y0), y1))), y2), 0)) -> c5(MARK(cons(s(from(first(s(y0), y1))), y2)))
   MARK(first(cons(s(from(first(cons(y0, y1), y2))), y3), 0)) -> c5(MARK(cons(s(from(first(cons(y0, y1), y2))), y3)))
   MARK(first(cons(s(from(from(y0))), y1), 0)) -> c5(MARK(cons(s(from(from(y0))), y1)))
   MARK(first(cons(s(from(from(first(y0, y1)))), y2), 0)) -> c5(MARK(cons(s(from(from(first(y0, y1)))), y2)))
   MARK(first(cons(s(from(from(from(y0)))), y1), 0)) -> c5(MARK(cons(s(from(from(from(y0)))), y1)))
   MARK(first(cons(s(from(from(s(y0)))), y1), 0)) -> c5(MARK(cons(s(from(from(s(y0)))), y1)))
   MARK(first(cons(s(from(from(cons(y0, y1)))), y2), 0)) -> c5(MARK(cons(s(from(from(cons(y0, y1)))), y2)))
   MARK(first(cons(s(from(from(0))), y0), 0)) -> c5(MARK(cons(s(from(from(0))), y0)))
   MARK(first(cons(s(from(from(nil))), y0), 0)) -> c5(MARK(cons(s(from(from(nil))), y0)))
S tuples:
   MARK(first(x0, nil)) -> c5(MARK(x0))
   MARK(first(x0, s(z0))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), x1)) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, s(z0))) -> c6(MARK(s(z0)))
   MARK(first(0, x1)) -> c6(MARK(x1))
   MARK(first(nil, x1)) -> c6(MARK(x1))
   MARK(first(cons(z0, z1), x1)) -> c6(MARK(x1))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, first(x1, from(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, 0))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(x0))
   MARK(first(x0, first(x1, nil))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(x0))
   MARK(first(x0, first(x1, s(z0)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(x0))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(x0))
   MARK(first(x0, first(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(x0))
   MARK(first(x0, first(from(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(0, x2))) -> c5(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(x0))
   MARK(first(x0, first(nil, x2))) -> c5(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(x0))
   MARK(first(x0, first(s(z0), x2))) -> c5(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(x0))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(x0))
   MARK(first(first(z0, z1), first(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(z0, z1)))
   MARK(first(from(z0), first(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(from(z0)))
   MARK(first(s(z0), first(x1, x2))) -> c5(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(s(z0)))
   MARK(first(x0, first(x1, x2))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, from(x1))) -> c5(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(x0))
   MARK(first(x0, from(first(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(x0))
   MARK(first(x0, from(from(z0)))) -> c5(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(x0))
   MARK(first(x0, from(0))) -> c5(A__FIRST(mark(x0), a__from(0)), MARK(x0))
   MARK(first(x0, from(nil))) -> c5(A__FIRST(mark(x0), a__from(nil)), MARK(x0))
   MARK(first(x0, from(s(z0)))) -> c5(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(x0))
   MARK(first(x0, from(cons(z0, z1)))) -> c5(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(x0))
   MARK(first(first(z0, z1), from(x1))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(first(z0, z1)))
   MARK(first(from(z0), from(x1))) -> c5(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(z0)))
   MARK(first(s(z0), from(x1))) -> c5(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(s(z0)))
   MARK(first(x0, from(x1))) -> c5(MARK(x0))
   MARK(first(cons(z0, z1), from(x1))) -> c5(MARK(cons(z0, z1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(x0))
   MARK(first(x0, cons(from(z0), x2))) -> c5(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(s(z0), x2))) -> c5(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(x0))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c5(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(x0))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c5(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(first(z0, z1)))
   MARK(first(from(z0), cons(x1, x2))) -> c5(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(from(z0)))
   MARK(first(s(z0), cons(x1, x2))) -> c5(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(s(z0)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c5(MARK(cons(z0, z1)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(first(x0, first(z0, z1))))
   MARK(first(first(x0, from(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(first(x0, from(z0))))
   MARK(first(first(x0, 0), x2)) -> c5(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(first(x0, 0)))
   MARK(first(first(x0, nil), x2)) -> c5(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(first(x0, nil)))
   MARK(first(first(x0, s(z0)), x2)) -> c5(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(first(x0, s(z0))))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c5(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(first(x0, cons(z0, z1))))
   MARK(first(first(first(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(first(first(z0, z1), x1)))
   MARK(first(first(from(z0), x1), x2)) -> c5(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(first(from(z0), x1)))
   MARK(first(first(0, x1), x2)) -> c5(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(first(0, x1)))
   MARK(first(first(nil, x1), x2)) -> c5(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(first(nil, x1)))
   MARK(first(first(s(z0), x1), x2)) -> c5(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(first(s(z0), x1)))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c5(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(first(cons(z0, z1), x1)))
   MARK(first(first(x0, x1), 0)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), nil)) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), s(z0))) -> c5(MARK(first(x0, x1)))
   MARK(first(first(x0, x1), x2)) -> c5(MARK(first(x0, x1)))
   MARK(first(from(first(z0, z1)), x1)) -> c5(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(from(first(z0, z1))))
   MARK(first(from(from(z0)), x1)) -> c5(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(from(from(z0))))
   MARK(first(from(s(z0)), x1)) -> c5(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(from(s(z0))))
   MARK(first(from(cons(z0, z1)), x1)) -> c5(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(from(cons(z0, z1))))
   MARK(first(from(x0), x1)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), 0)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), nil)) -> c5(MARK(from(x0)))
   MARK(first(from(x0), s(z0))) -> c5(MARK(from(x0)))
   MARK(first(s(first(z0, z1)), x1)) -> c5(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(s(first(z0, z1))))
   MARK(first(s(from(z0)), x1)) -> c5(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(s(from(z0))))
   MARK(first(s(s(z0)), x1)) -> c5(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(s(s(z0))))
   MARK(first(s(cons(z0, z1)), x1)) -> c5(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(s(cons(z0, z1))))
   MARK(first(s(x0), x1)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), 0)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), nil)) -> c5(MARK(s(x0)))
   MARK(first(s(x0), s(z0))) -> c5(MARK(s(x0)))
   MARK(first(x0, first(x1, first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__first(mark(z0), mark(z1)))), MARK(first(x1, first(z0, z1))))
   MARK(first(x0, first(x1, from(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), a__from(mark(z0)))), MARK(first(x1, from(z0))))
   MARK(first(x0, first(x1, 0))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), 0)), MARK(first(x1, 0)))
   MARK(first(x0, first(x1, nil))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), nil)), MARK(first(x1, nil)))
   MARK(first(x0, first(x1, s(z0)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), s(mark(z0)))), MARK(first(x1, s(z0))))
   MARK(first(x0, first(x1, cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__first(mark(x1), cons(mark(z0), z1))), MARK(first(x1, cons(z0, z1))))
   MARK(first(x0, first(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(a__first(mark(z0), mark(z1)), mark(x2))), MARK(first(first(z0, z1), x2)))
   MARK(first(x0, first(from(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(a__from(mark(z0)), mark(x2))), MARK(first(from(z0), x2)))
   MARK(first(x0, first(0, x2))) -> c6(A__FIRST(mark(x0), a__first(0, mark(x2))), MARK(first(0, x2)))
   MARK(first(x0, first(nil, x2))) -> c6(A__FIRST(mark(x0), a__first(nil, mark(x2))), MARK(first(nil, x2)))
   MARK(first(x0, first(s(z0), x2))) -> c6(A__FIRST(mark(x0), a__first(s(mark(z0)), mark(x2))), MARK(first(s(z0), x2)))
   MARK(first(x0, first(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), a__first(cons(mark(z0), z1), mark(x2))), MARK(first(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), first(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(from(z0), first(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(s(z0), first(x1, x2))) -> c6(A__FIRST(s(mark(z0)), a__first(mark(x1), mark(x2))), MARK(first(x1, x2)))
   MARK(first(x0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(0, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(nil, first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(cons(z0, z1), first(x1, x2))) -> c6(MARK(first(x1, x2)))
   MARK(first(x0, from(x1))) -> c6(A__FIRST(mark(x0), cons(mark(mark(x1)), from(s(mark(x1))))), MARK(from(x1)))
   MARK(first(x0, from(first(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(a__first(mark(z0), mark(z1)))), MARK(from(first(z0, z1))))
   MARK(first(x0, from(from(z0)))) -> c6(A__FIRST(mark(x0), a__from(a__from(mark(z0)))), MARK(from(from(z0))))
   MARK(first(x0, from(s(z0)))) -> c6(A__FIRST(mark(x0), a__from(s(mark(z0)))), MARK(from(s(z0))))
   MARK(first(x0, from(cons(z0, z1)))) -> c6(A__FIRST(mark(x0), a__from(cons(mark(z0), z1))), MARK(from(cons(z0, z1))))
   MARK(first(first(z0, z1), from(x1))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(from(z0), from(x1))) -> c6(A__FIRST(a__from(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(s(z0), from(x1))) -> c6(A__FIRST(s(mark(z0)), a__from(mark(x1))), MARK(from(x1)))
   MARK(first(x0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(0, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(nil, from(x1))) -> c6(MARK(from(x1)))
   MARK(first(cons(z0, z1), from(x1))) -> c6(MARK(from(x1)))
   MARK(first(x0, cons(first(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(a__first(mark(z0), mark(z1)), x2)), MARK(cons(first(z0, z1), x2)))
   MARK(first(x0, cons(from(z0), x2))) -> c6(A__FIRST(mark(x0), cons(a__from(mark(z0)), x2)), MARK(cons(from(z0), x2)))
   MARK(first(x0, cons(s(z0), x2))) -> c6(A__FIRST(mark(x0), cons(s(mark(z0)), x2)), MARK(cons(s(z0), x2)))
   MARK(first(x0, cons(cons(z0, z1), x2))) -> c6(A__FIRST(mark(x0), cons(cons(mark(z0), z1), x2)), MARK(cons(cons(z0, z1), x2)))
   MARK(first(first(z0, z1), cons(x1, x2))) -> c6(A__FIRST(a__first(mark(z0), mark(z1)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(from(z0), cons(x1, x2))) -> c6(A__FIRST(a__from(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(s(z0), cons(x1, x2))) -> c6(A__FIRST(s(mark(z0)), cons(mark(x1), x2)), MARK(cons(x1, x2)))
   MARK(first(x0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(0, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(nil, cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(cons(z0, z1), cons(x1, x2))) -> c6(MARK(cons(x1, x2)))
   MARK(first(first(x0, first(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__first(mark(z0), mark(z1))), mark(x2)), MARK(x2))
   MARK(first(first(x0, from(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), a__from(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, 0), x2)) -> c6(A__FIRST(a__first(mark(x0), 0), mark(x2)), MARK(x2))
   MARK(first(first(x0, nil), x2)) -> c6(A__FIRST(a__first(mark(x0), nil), mark(x2)), MARK(x2))
   MARK(first(first(x0, s(z0)), x2)) -> c6(A__FIRST(a__first(mark(x0), s(mark(z0))), mark(x2)), MARK(x2))
   MARK(first(first(x0, cons(z0, z1)), x2)) -> c6(A__FIRST(a__first(mark(x0), cons(mark(z0), z1)), mark(x2)), MARK(x2))
   MARK(first(first(first(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(a__first(mark(z0), mark(z1)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(from(z0), x1), x2)) -> c6(A__FIRST(a__first(a__from(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(0, x1), x2)) -> c6(A__FIRST(a__first(0, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(nil, x1), x2)) -> c6(A__FIRST(a__first(nil, mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(s(z0), x1), x2)) -> c6(A__FIRST(a__first(s(mark(z0)), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(cons(z0, z1), x1), x2)) -> c6(A__FIRST(a__first(cons(mark(z0), z1), mark(x1)), mark(x2)), MARK(x2))
   MARK(first(first(x0, x1), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(first(x0, x1), x2)) -> c6(MARK(x2))
   MARK(first(from(first(z0, z1)), x1)) -> c6(A__FIRST(a__from(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(from(from(z0)), x1)) -> c6(A__FIRST(a__from(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(0), x1)) -> c6(A__FIRST(a__from(0), mark(x1)), MARK(x1))
   MARK(first(from(nil), x1)) -> c6(A__FIRST(a__from(nil), mark(x1)), MARK(x1))
   MARK(first(from(s(z0)), x1)) -> c6(A__FIRST(a__from(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(from(cons(z0, z1)), x1)) -> c6(A__FIRST(a__from(cons(mark(z0), z1)), mark(x1)), MARK(x1))
   MARK(first(from(x0), s(z0))) -> c6(MARK(s(z0)))
   MARK(first(from(x0), x1)) -> c6(MARK(x1))
   MARK(first(s(first(z0, z1)), x1)) -> c6(A__FIRST(s(a__first(mark(z0), mark(z1))), mark(x1)), MARK(x1))
   MARK(first(s(from(z0)), x1)) -> c6(A__FIRST(s(a__from(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(0), x1)) -> c6(A__FIRST(s(0), mark(x1)), MARK(x1))
   MARK(first(s(nil), x1)) -> c6(A__FIRST(s(nil), mark(x1)), MARK(x1))
   MARK(first(s(s(z0)), x1)) -> c6(A__FIRST(s(s(mark(z0))), mark(x1)), MARK(x1))
   MARK(first(s(cons(z0, z1)), x1)) -> c6(A__FIRST(s(cons(mark(z0), z1)), mark(x1)), MARK(x1))
   MARK(first(s(x0), s(z0))) -> c6(MARK(s(z0)))
   A__FIRST(s(z0), cons(from(y0), z2)) -> c1(MARK(from(y0)))
   A__FIRST(s(z0), cons(s(y0), z2)) -> c1(MARK(s(y0)))
   A__FIRST(s(z0), cons(cons(y0, y1), z2)) -> c1(MARK(cons(y0, y1)))
   A__FIRST(s(z0), cons(first(y0, 0), z2)) -> c1(MARK(first(y0, 0)))
   A__FIRST(s(z0), cons(first(y0, nil), z2)) -> c1(MARK(first(y0, nil)))
   A__FIRST(s(z0), cons(first(y0, s(y1)), z2)) -> c1(MARK(first(y0, s(y1))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), y2), z2)) -> c1(MARK(first(cons(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(0, y0), z2)) -> c1(MARK(first(0, y0)))
   A__FIRST(s(z0), cons(first(nil, y0), z2)) -> c1(MARK(first(nil, y0)))
   A__FIRST(s(z0), cons(first(y0, first(y1, first(y2, y3))), z2)) -> c1(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FIRST(s(z0), cons(first(y0, first(y1, from(y2))), z2)) -> c1(MARK(first(y0, first(y1, from(y2)))))
   A__FIRST(s(z0), cons(first(y0, first(y1, 0)), z2)) -> c1(MARK(first(y0, first(y1, 0))))
   A__FIRST(s(z0), cons(first(y0, first(y1, nil)), z2)) -> c1(MARK(first(y0, first(y1, nil))))
   A__FIRST(s(z0), cons(first(y0, first(y1, s(y2))), z2)) -> c1(MARK(first(y0, first(y1, s(y2)))))
   A__FIRST(s(z0), cons(first(y0, first(y1, cons(y2, y3))), z2)) -> c1(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FIRST(s(z0), cons(first(y0, first(first(y1, y2), y3)), z2)) -> c1(MARK(first(y0, first(first(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(y0, first(from(y1), y2)), z2)) -> c1(MARK(first(y0, first(from(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, first(0, y1)), z2)) -> c1(MARK(first(y0, first(0, y1))))
   A__FIRST(s(z0), cons(first(y0, first(nil, y1)), z2)) -> c1(MARK(first(y0, first(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, first(s(y1), y2)), z2)) -> c1(MARK(first(y0, first(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, first(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), first(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), first(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), first(y1, y2)), z2)) -> c1(MARK(first(from(y0), first(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), first(y1, y2)), z2)) -> c1(MARK(first(s(y0), first(y1, y2))))
   A__FIRST(s(z0), cons(first(y0, first(y1, y2)), z2)) -> c1(MARK(first(y0, first(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), first(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FIRST(s(z0), cons(first(y0, from(y1)), z2)) -> c1(MARK(first(y0, from(y1))))
   A__FIRST(s(z0), cons(first(y0, from(first(y1, y2))), z2)) -> c1(MARK(first(y0, from(first(y1, y2)))))
   A__FIRST(s(z0), cons(first(y0, from(from(y1))), z2)) -> c1(MARK(first(y0, from(from(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(0)), z2)) -> c1(MARK(first(y0, from(0))))
   A__FIRST(s(z0), cons(first(y0, from(nil)), z2)) -> c1(MARK(first(y0, from(nil))))
   A__FIRST(s(z0), cons(first(y0, from(s(y1))), z2)) -> c1(MARK(first(y0, from(s(y1)))))
   A__FIRST(s(z0), cons(first(y0, from(cons(y1, y2))), z2)) -> c1(MARK(first(y0, from(cons(y1, y2)))))
   A__FIRST(s(z0), cons(first(first(y0, y1), from(y2)), z2)) -> c1(MARK(first(first(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(from(y0), from(y1)), z2)) -> c1(MARK(first(from(y0), from(y1))))
   A__FIRST(s(z0), cons(first(s(y0), from(y1)), z2)) -> c1(MARK(first(s(y0), from(y1))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), from(y2)), z2)) -> c1(MARK(first(cons(y0, y1), from(y2))))
   A__FIRST(s(z0), cons(first(y0, cons(first(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(y0, cons(from(y1), y2)), z2)) -> c1(MARK(first(y0, cons(from(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(0, y1)), z2)) -> c1(MARK(first(y0, cons(0, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(nil, y1)), z2)) -> c1(MARK(first(y0, cons(nil, y1))))
   A__FIRST(s(z0), cons(first(y0, cons(s(y1), y2)), z2)) -> c1(MARK(first(y0, cons(s(y1), y2))))
   A__FIRST(s(z0), cons(first(y0, cons(cons(y1, y2), y3)), z2)) -> c1(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FIRST(s(z0), cons(first(first(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(from(y0), cons(y1, y2)), z2)) -> c1(MARK(first(from(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(s(y0), cons(y1, y2)), z2)) -> c1(MARK(first(s(y0), cons(y1, y2))))
   A__FIRST(s(z0), cons(first(cons(y0, y1), cons(y2, y3)), z2)) -> c1(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FIRST(s(z0), cons(first(first(y0, first(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(y0, from(y1)), y2), z2)) -> c1(MARK(first(first(y0, from(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, 0), y1), z2)) -> c1(MARK(first(first(y0, 0), y1)))
   A__FIRST(s(z0), cons(first(first(y0, nil), y1), z2)) -> c1(MARK(first(first(y0, nil), y1)))
   A__FIRST(s(z0), cons(first(first(y0, s(y1)), y2), z2)) -> c1(MARK(first(first(y0, s(y1)), y2)))
   A__FIRST(s(z0), cons(first(first(y0, cons(y1, y2)), y3), z2)) -> c1(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FIRST(s(z0), cons(first(first(first(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(first(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(from(y0), y1), y2), z2)) -> c1(MARK(first(first(from(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(0, y0), y1), z2)) -> c1(MARK(first(first(0, y0), y1)))
   A__FIRST(s(z0), cons(first(first(nil, y0), y1), z2)) -> c1(MARK(first(first(nil, y0), y1)))
   A__FIRST(s(z0), cons(first(first(s(y0), y1), y2), z2)) -> c1(MARK(first(first(s(y0), y1), y2)))
   A__FIRST(s(z0), cons(first(first(cons(y0, y1), y2), y3), z2)) -> c1(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FIRST(s(z0), cons(first(first(y0, y1), 0), z2)) -> c1(MARK(first(first(y0, y1), 0)))
   A__FIRST(s(z0), cons(first(first(y0, y1), nil), z2)) -> c1(MARK(first(first(y0, y1), nil)))
   A__FIRST(s(z0), cons(first(first(y0, y1), s(y2)), z2)) -> c1(MARK(first(first(y0, y1), s(y2))))
   A__FIRST(s(z0), cons(first(first(y0, y1), y2), z2)) -> c1(MARK(first(first(y0, y1), y2)))
   A__FIRST(s(z0), cons(first(from(first(y0, y1)), y2), z2)) -> c1(MARK(first(from(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(from(y0)), y1), z2)) -> c1(MARK(first(from(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(0), y0), z2)) -> c1(MARK(first(from(0), y0)))
   A__FIRST(s(z0), cons(first(from(nil), y0), z2)) -> c1(MARK(first(from(nil), y0)))
   A__FIRST(s(z0), cons(first(from(s(y0)), y1), z2)) -> c1(MARK(first(from(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(from(cons(y0, y1)), y2), z2)) -> c1(MARK(first(from(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(from(y0), y1), z2)) -> c1(MARK(first(from(y0), y1)))
   A__FIRST(s(z0), cons(first(from(y0), 0), z2)) -> c1(MARK(first(from(y0), 0)))
   A__FIRST(s(z0), cons(first(from(y0), nil), z2)) -> c1(MARK(first(from(y0), nil)))
   A__FIRST(s(z0), cons(first(from(y0), s(y1)), z2)) -> c1(MARK(first(from(y0), s(y1))))
   A__FIRST(s(z0), cons(first(s(first(y0, y1)), y2), z2)) -> c1(MARK(first(s(first(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(from(y0)), y1), z2)) -> c1(MARK(first(s(from(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(0), y0), z2)) -> c1(MARK(first(s(0), y0)))
   A__FIRST(s(z0), cons(first(s(nil), y0), z2)) -> c1(MARK(first(s(nil), y0)))
   A__FIRST(s(z0), cons(first(s(s(y0)), y1), z2)) -> c1(MARK(first(s(s(y0)), y1)))
   A__FIRST(s(z0), cons(first(s(cons(y0, y1)), y2), z2)) -> c1(MARK(first(s(cons(y0, y1)), y2)))
   A__FIRST(s(z0), cons(first(s(y0), y1), z2)) -> c1(MARK(first(s(y0), y1)))
   A__FIRST(s(z0), cons(first(s(y0), 0), z2)) -> c1(MARK(first(s(y0), 0)))
   A__FIRST(s(z0), cons(first(s(y0), nil), z2)) -> c1(MARK(first(s(y0), nil)))
   A__FIRST(s(z0), cons(first(s(y0), s(y1)), z2)) -> c1(MARK(first(s(y0), s(y1))))
   A__FIRST(s(z0), cons(first(0, first(y0, y1)), z2)) -> c1(MARK(first(0, first(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, first(y0, y1)), z2)) -> c1(MARK(first(nil, first(y0, y1))))
   A__FIRST(s(z0), cons(first(0, from(y0)), z2)) -> c1(MARK(first(0, from(y0))))
   A__FIRST(s(z0), cons(first(nil, from(y0)), z2)) -> c1(MARK(first(nil, from(y0))))
   A__FIRST(s(z0), cons(first(y0, cons(y1, y2)), z2)) -> c1(MARK(first(y0, cons(y1, y2))))
   A__FIRST(s(z0), cons(first(0, cons(y0, y1)), z2)) -> c1(MARK(first(0, cons(y0, y1))))
   A__FIRST(s(z0), cons(first(nil, cons(y0, y1)), z2)) -> c1(MARK(first(nil, cons(y0, y1))))
   MARK(first(x0, cons(0, x2))) -> c5(MARK(x0))
   MARK(first(x0, cons(nil, x2))) -> c5(MARK(x0))
   A__FROM(from(y0)) -> c3(MARK(from(y0)))
   A__FROM(s(y0)) -> c3(MARK(s(y0)))
   A__FROM(cons(y0, y1)) -> c3(MARK(cons(y0, y1)))
   A__FROM(first(y0, 0)) -> c3(MARK(first(y0, 0)))
   A__FROM(first(y0, nil)) -> c3(MARK(first(y0, nil)))
   A__FROM(first(y0, s(y1))) -> c3(MARK(first(y0, s(y1))))
   A__FROM(first(cons(y0, y1), y2)) -> c3(MARK(first(cons(y0, y1), y2)))
   A__FROM(first(0, y0)) -> c3(MARK(first(0, y0)))
   A__FROM(first(nil, y0)) -> c3(MARK(first(nil, y0)))
   A__FROM(first(y0, first(y1, first(y2, y3)))) -> c3(MARK(first(y0, first(y1, first(y2, y3)))))
   A__FROM(first(y0, first(y1, from(y2)))) -> c3(MARK(first(y0, first(y1, from(y2)))))
   A__FROM(first(y0, first(y1, 0))) -> c3(MARK(first(y0, first(y1, 0))))
   A__FROM(first(y0, first(y1, nil))) -> c3(MARK(first(y0, first(y1, nil))))
   A__FROM(first(y0, first(y1, s(y2)))) -> c3(MARK(first(y0, first(y1, s(y2)))))
   A__FROM(first(y0, first(y1, cons(y2, y3)))) -> c3(MARK(first(y0, first(y1, cons(y2, y3)))))
   A__FROM(first(y0, first(first(y1, y2), y3))) -> c3(MARK(first(y0, first(first(y1, y2), y3))))
   A__FROM(first(y0, first(from(y1), y2))) -> c3(MARK(first(y0, first(from(y1), y2))))
   A__FROM(first(y0, first(0, y1))) -> c3(MARK(first(y0, first(0, y1))))
   A__FROM(first(y0, first(nil, y1))) -> c3(MARK(first(y0, first(nil, y1))))
   A__FROM(first(y0, first(s(y1), y2))) -> c3(MARK(first(y0, first(s(y1), y2))))
   A__FROM(first(y0, first(cons(y1, y2), y3))) -> c3(MARK(first(y0, first(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), first(y2, y3))) -> c3(MARK(first(first(y0, y1), first(y2, y3))))
   A__FROM(first(from(y0), first(y1, y2))) -> c3(MARK(first(from(y0), first(y1, y2))))
   A__FROM(first(s(y0), first(y1, y2))) -> c3(MARK(first(s(y0), first(y1, y2))))
   A__FROM(first(y0, first(y1, y2))) -> c3(MARK(first(y0, first(y1, y2))))
   A__FROM(first(cons(y0, y1), first(y2, y3))) -> c3(MARK(first(cons(y0, y1), first(y2, y3))))
   A__FROM(first(y0, from(y1))) -> c3(MARK(first(y0, from(y1))))
   A__FROM(first(y0, from(first(y1, y2)))) -> c3(MARK(first(y0, from(first(y1, y2)))))
   A__FROM(first(y0, from(from(y1)))) -> c3(MARK(first(y0, from(from(y1)))))
   A__FROM(first(y0, from(0))) -> c3(MARK(first(y0, from(0))))
   A__FROM(first(y0, from(nil))) -> c3(MARK(first(y0, from(nil))))
   A__FROM(first(y0, from(s(y1)))) -> c3(MARK(first(y0, from(s(y1)))))
   A__FROM(first(y0, from(cons(y1, y2)))) -> c3(MARK(first(y0, from(cons(y1, y2)))))
   A__FROM(first(first(y0, y1), from(y2))) -> c3(MARK(first(first(y0, y1), from(y2))))
   A__FROM(first(from(y0), from(y1))) -> c3(MARK(first(from(y0), from(y1))))
   A__FROM(first(s(y0), from(y1))) -> c3(MARK(first(s(y0), from(y1))))
   A__FROM(first(cons(y0, y1), from(y2))) -> c3(MARK(first(cons(y0, y1), from(y2))))
   A__FROM(first(y0, cons(first(y1, y2), y3))) -> c3(MARK(first(y0, cons(first(y1, y2), y3))))
   A__FROM(first(y0, cons(from(y1), y2))) -> c3(MARK(first(y0, cons(from(y1), y2))))
   A__FROM(first(y0, cons(s(y1), y2))) -> c3(MARK(first(y0, cons(s(y1), y2))))
   A__FROM(first(y0, cons(cons(y1, y2), y3))) -> c3(MARK(first(y0, cons(cons(y1, y2), y3))))
   A__FROM(first(first(y0, y1), cons(y2, y3))) -> c3(MARK(first(first(y0, y1), cons(y2, y3))))
   A__FROM(first(from(y0), cons(y1, y2))) -> c3(MARK(first(from(y0), cons(y1, y2))))
   A__FROM(first(s(y0), cons(y1, y2))) -> c3(MARK(first(s(y0), cons(y1, y2))))
   A__FROM(first(cons(y0, y1), cons(y2, y3))) -> c3(MARK(first(cons(y0, y1), cons(y2, y3))))
   A__FROM(first(first(y0, first(y1, y2)), y3)) -> c3(MARK(first(first(y0, first(y1, y2)), y3)))
   A__FROM(first(first(y0, from(y1)), y2)) -> c3(MARK(first(first(y0, from(y1)), y2)))
   A__FROM(first(first(y0, 0), y1)) -> c3(MARK(first(first(y0, 0), y1)))
   A__FROM(first(first(y0, nil), y1)) -> c3(MARK(first(first(y0, nil), y1)))
   A__FROM(first(first(y0, s(y1)), y2)) -> c3(MARK(first(first(y0, s(y1)), y2)))
   A__FROM(first(first(y0, cons(y1, y2)), y3)) -> c3(MARK(first(first(y0, cons(y1, y2)), y3)))
   A__FROM(first(first(first(y0, y1), y2), y3)) -> c3(MARK(first(first(first(y0, y1), y2), y3)))
   A__FROM(first(first(from(y0), y1), y2)) -> c3(MARK(first(first(from(y0), y1), y2)))
   A__FROM(first(first(0, y0), y1)) -> c3(MARK(first(first(0, y0), y1)))
   A__FROM(first(first(nil, y0), y1)) -> c3(MARK(first(first(nil, y0), y1)))
   A__FROM(first(first(s(y0), y1), y2)) -> c3(MARK(first(first(s(y0), y1), y2)))
   A__FROM(first(first(cons(y0, y1), y2), y3)) -> c3(MARK(first(first(cons(y0, y1), y2), y3)))
   A__FROM(first(first(y0, y1), 0)) -> c3(MARK(first(first(y0, y1), 0)))
   A__FROM(first(first(y0, y1), nil)) -> c3(MARK(first(first(y0, y1), nil)))
   A__FROM(first(first(y0, y1), s(y2))) -> c3(MARK(first(first(y0, y1), s(y2))))
   A__FROM(first(first(y0, y1), y2)) -> c3(MARK(first(first(y0, y1), y2)))
   A__FROM(first(from(first(y0, y1)), y2)) -> c3(MARK(first(from(first(y0, y1)), y2)))
   A__FROM(first(from(from(y0)), y1)) -> c3(MARK(first(from(from(y0)), y1)))
   A__FROM(first(from(0), y0)) -> c3(MARK(first(from(0), y0)))
   A__FROM(first(from(nil), y0)) -> c3(MARK(first(from(nil), y0)))
   A__FROM(first(from(s(y0)), y1)) -> c3(MARK(first(from(s(y0)), y1)))
   A__FROM(first(from(cons(y0, y1)), y2)) -> c3(MARK(first(from(cons(y0, y1)), y2)))
   A__FROM(first(from(y0), y1)) -> c3(MARK(first(from(y0), y1)))
   A__FROM(first(from(y0), 0)) -> c3(MARK(first(from(y0), 0)))
   A__FROM(first(from(y0), nil)) -> c3(MARK(first(from(y0), nil)))
   A__FROM(first(from(y0), s(y1))) -> c3(MARK(first(from(y0), s(y1))))
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   MARK(first(cons(s(first(y0, from(from(y1)))), y2), 0)) -> c5(MARK(cons(s(first(y0, from(from(y1)))), y2)))
   MARK(first(cons(s(first(y0, from(0))), y1), 0)) -> c5(MARK(cons(s(first(y0, from(0))), y1)))
   MARK(first(cons(s(first(y0, from(nil))), y1), 0)) -> c5(MARK(cons(s(first(y0, from(nil))), y1)))
   MARK(first(cons(s(first(y0, from(s(y1)))), y2), 0)) -> c5(MARK(cons(s(first(y0, from(s(y1)))), y2)))
   MARK(first(cons(s(first(y0, from(cons(y1, y2)))), y3), 0)) -> c5(MARK(cons(s(first(y0, from(cons(y1, y2)))), y3)))
   MARK(first(cons(s(first(first(y0, y1), from(y2))), y3), 0)) -> c5(MARK(cons(s(first(first(y0, y1), from(y2))), y3)))
   MARK(first(cons(s(first(from(y0), from(y1))), y2), 0)) -> c5(MARK(cons(s(first(from(y0), from(y1))), y2)))
   MARK(first(cons(s(first(s(y0), from(y1))), y2), 0)) -> c5(MARK(cons(s(first(s(y0), from(y1))), y2)))
   MARK(first(cons(s(first(cons(y0, y1), from(y2))), y3), 0)) -> c5(MARK(cons(s(first(cons(y0, y1), from(y2))), y3)))
   MARK(first(cons(s(first(y0, cons(first(y1, y2), y3))), y4), 0)) -> c5(MARK(cons(s(first(y0, cons(first(y1, y2), y3))), y4)))
   MARK(first(cons(s(first(y0, cons(from(y1), y2))), y3), 0)) -> c5(MARK(cons(s(first(y0, cons(from(y1), y2))), y3)))
   MARK(first(cons(s(first(y0, cons(s(y1), y2))), y3), 0)) -> c5(MARK(cons(s(first(y0, cons(s(y1), y2))), y3)))
   MARK(first(cons(s(first(y0, cons(cons(y1, y2), y3))), y4), 0)) -> c5(MARK(cons(s(first(y0, cons(cons(y1, y2), y3))), y4)))
   MARK(first(cons(s(first(first(y0, y1), cons(y2, y3))), y4), 0)) -> c5(MARK(cons(s(first(first(y0, y1), cons(y2, y3))), y4)))
   MARK(first(cons(s(first(from(y0), cons(y1, y2))), y3), 0)) -> c5(MARK(cons(s(first(from(y0), cons(y1, y2))), y3)))
   MARK(first(cons(s(first(s(y0), cons(y1, y2))), y3), 0)) -> c5(MARK(cons(s(first(s(y0), cons(y1, y2))), y3)))
   MARK(first(cons(s(first(cons(y0, y1), cons(y2, y3))), y4), 0)) -> c5(MARK(cons(s(first(cons(y0, y1), cons(y2, y3))), y4)))
   MARK(first(cons(s(first(first(y0, first(y1, y2)), y3)), y4), 0)) -> c5(MARK(cons(s(first(first(y0, first(y1, y2)), y3)), y4)))
   MARK(first(cons(s(first(first(y0, from(y1)), y2)), y3), 0)) -> c5(MARK(cons(s(first(first(y0, from(y1)), y2)), y3)))
   MARK(first(cons(s(first(first(y0, 0), y1)), y2), 0)) -> c5(MARK(cons(s(first(first(y0, 0), y1)), y2)))
   MARK(first(cons(s(first(first(y0, nil), y1)), y2), 0)) -> c5(MARK(cons(s(first(first(y0, nil), y1)), y2)))
   MARK(first(cons(s(first(first(y0, s(y1)), y2)), y3), 0)) -> c5(MARK(cons(s(first(first(y0, s(y1)), y2)), y3)))
   MARK(first(cons(s(first(first(y0, cons(y1, y2)), y3)), y4), 0)) -> c5(MARK(cons(s(first(first(y0, cons(y1, y2)), y3)), y4)))
   MARK(first(cons(s(first(first(first(y0, y1), y2), y3)), y4), 0)) -> c5(MARK(cons(s(first(first(first(y0, y1), y2), y3)), y4)))
   MARK(first(cons(s(first(first(from(y0), y1), y2)), y3), 0)) -> c5(MARK(cons(s(first(first(from(y0), y1), y2)), y3)))
   MARK(first(cons(s(first(first(0, y0), y1)), y2), 0)) -> c5(MARK(cons(s(first(first(0, y0), y1)), y2)))
   MARK(first(cons(s(first(first(nil, y0), y1)), y2), 0)) -> c5(MARK(cons(s(first(first(nil, y0), y1)), y2)))
   MARK(first(cons(s(first(first(s(y0), y1), y2)), y3), 0)) -> c5(MARK(cons(s(first(first(s(y0), y1), y2)), y3)))
   MARK(first(cons(s(first(first(cons(y0, y1), y2), y3)), y4), 0)) -> c5(MARK(cons(s(first(first(cons(y0, y1), y2), y3)), y4)))
   MARK(first(cons(s(first(first(y0, y1), 0)), y2), 0)) -> c5(MARK(cons(s(first(first(y0, y1), 0)), y2)))
   MARK(first(cons(s(first(first(y0, y1), nil)), y2), 0)) -> c5(MARK(cons(s(first(first(y0, y1), nil)), y2)))
   MARK(first(cons(s(first(first(y0, y1), s(y2))), y3), 0)) -> c5(MARK(cons(s(first(first(y0, y1), s(y2))), y3)))
   MARK(first(cons(s(first(first(y0, y1), y2)), y3), 0)) -> c5(MARK(cons(s(first(first(y0, y1), y2)), y3)))
   MARK(first(cons(s(first(from(first(y0, y1)), y2)), y3), 0)) -> c5(MARK(cons(s(first(from(first(y0, y1)), y2)), y3)))
   MARK(first(cons(s(first(from(from(y0)), y1)), y2), 0)) -> c5(MARK(cons(s(first(from(from(y0)), y1)), y2)))
   MARK(first(cons(s(first(from(s(y0)), y1)), y2), 0)) -> c5(MARK(cons(s(first(from(s(y0)), y1)), y2)))
   MARK(first(cons(s(first(from(cons(y0, y1)), y2)), y3), 0)) -> c5(MARK(cons(s(first(from(cons(y0, y1)), y2)), y3)))
   MARK(first(cons(s(first(from(y0), y1)), y2), 0)) -> c5(MARK(cons(s(first(from(y0), y1)), y2)))
   MARK(first(cons(s(first(from(y0), 0)), y1), 0)) -> c5(MARK(cons(s(first(from(y0), 0)), y1)))
   MARK(first(cons(s(first(from(y0), nil)), y1), 0)) -> c5(MARK(cons(s(first(from(y0), nil)), y1)))
   MARK(first(cons(s(first(from(y0), s(y1))), y2), 0)) -> c5(MARK(cons(s(first(from(y0), s(y1))), y2)))
   MARK(first(cons(s(first(s(first(y0, y1)), y2)), y3), 0)) -> c5(MARK(cons(s(first(s(first(y0, y1)), y2)), y3)))
   MARK(first(cons(s(first(s(from(y0)), y1)), y2), 0)) -> c5(MARK(cons(s(first(s(from(y0)), y1)), y2)))
   MARK(first(cons(s(first(s(0), y0)), y1), 0)) -> c5(MARK(cons(s(first(s(0), y0)), y1)))
   MARK(first(cons(s(first(s(nil), y0)), y1), 0)) -> c5(MARK(cons(s(first(s(nil), y0)), y1)))
   MARK(first(cons(s(first(s(s(y0)), y1)), y2), 0)) -> c5(MARK(cons(s(first(s(s(y0)), y1)), y2)))
   MARK(first(cons(s(first(s(cons(y0, y1)), y2)), y3), 0)) -> c5(MARK(cons(s(first(s(cons(y0, y1)), y2)), y3)))
   MARK(first(cons(s(first(s(y0), y1)), y2), 0)) -> c5(MARK(cons(s(first(s(y0), y1)), y2)))
   MARK(first(cons(s(first(s(y0), 0)), y1), 0)) -> c5(MARK(cons(s(first(s(y0), 0)), y1)))
   MARK(first(cons(s(first(s(y0), nil)), y1), 0)) -> c5(MARK(cons(s(first(s(y0), nil)), y1)))
   MARK(first(cons(s(first(s(y0), s(y1))), y2), 0)) -> c5(MARK(cons(s(first(s(y0), s(y1))), y2)))
   MARK(first(cons(s(first(0, first(y0, y1))), y2), 0)) -> c5(MARK(cons(s(first(0, first(y0, y1))), y2)))
   MARK(first(cons(s(first(nil, first(y0, y1))), y2), 0)) -> c5(MARK(cons(s(first(nil, first(y0, y1))), y2)))
   MARK(first(cons(s(first(0, from(y0))), y1), 0)) -> c5(MARK(cons(s(first(0, from(y0))), y1)))
   MARK(first(cons(s(first(nil, from(y0))), y1), 0)) -> c5(MARK(cons(s(first(nil, from(y0))), y1)))
   MARK(first(cons(s(first(y0, cons(y1, y2))), y3), 0)) -> c5(MARK(cons(s(first(y0, cons(y1, y2))), y3)))
   MARK(first(cons(s(first(0, cons(y0, y1))), y2), 0)) -> c5(MARK(cons(s(first(0, cons(y0, y1))), y2)))
   MARK(first(cons(s(first(nil, cons(y0, y1))), y2), 0)) -> c5(MARK(cons(s(first(nil, cons(y0, y1))), y2)))
   MARK(first(cons(s(first(from(0), y0)), y1), 0)) -> c5(MARK(cons(s(first(from(0), y0)), y1)))
   MARK(first(cons(s(first(from(nil), y0)), y1), 0)) -> c5(MARK(cons(s(first(from(nil), y0)), y1)))
   MARK(first(cons(s(first(y0, cons(0, y1))), y2), 0)) -> c5(MARK(cons(s(first(y0, cons(0, y1))), y2)))
   MARK(first(cons(s(first(y0, cons(nil, y1))), y2), 0)) -> c5(MARK(cons(s(first(y0, cons(nil, y1))), y2)))
   MARK(first(cons(s(from(s(y0))), y1), 0)) -> c5(MARK(cons(s(from(s(y0))), y1)))
   MARK(first(cons(s(from(cons(y0, y1))), y2), 0)) -> c5(MARK(cons(s(from(cons(y0, y1))), y2)))
   MARK(first(cons(s(from(first(y0, y1))), y2), 0)) -> c5(MARK(cons(s(from(first(y0, y1))), y2)))
   MARK(first(cons(s(from(first(y0, first(y1, y2)))), y3), 0)) -> c5(MARK(cons(s(from(first(y0, first(y1, y2)))), y3)))
   MARK(first(cons(s(from(first(y0, from(y1)))), y2), 0)) -> c5(MARK(cons(s(from(first(y0, from(y1)))), y2)))
   MARK(first(cons(s(from(first(y0, 0))), y1), 0)) -> c5(MARK(cons(s(from(first(y0, 0))), y1)))
   MARK(first(cons(s(from(first(y0, nil))), y1), 0)) -> c5(MARK(cons(s(from(first(y0, nil))), y1)))
   MARK(first(cons(s(from(first(y0, s(y1)))), y2), 0)) -> c5(MARK(cons(s(from(first(y0, s(y1)))), y2)))
   MARK(first(cons(s(from(first(y0, cons(y1, y2)))), y3), 0)) -> c5(MARK(cons(s(from(first(y0, cons(y1, y2)))), y3)))
   MARK(first(cons(s(from(first(first(y0, y1), y2))), y3), 0)) -> c5(MARK(cons(s(from(first(first(y0, y1), y2))), y3)))
   MARK(first(cons(s(from(first(from(y0), y1))), y2), 0)) -> c5(MARK(cons(s(from(first(from(y0), y1))), y2)))
   MARK(first(cons(s(from(first(0, y0))), y1), 0)) -> c5(MARK(cons(s(from(first(0, y0))), y1)))
   MARK(first(cons(s(from(first(nil, y0))), y1), 0)) -> c5(MARK(cons(s(from(first(nil, y0))), y1)))
   MARK(first(cons(s(from(first(s(y0), y1))), y2), 0)) -> c5(MARK(cons(s(from(first(s(y0), y1))), y2)))
   MARK(first(cons(s(from(first(cons(y0, y1), y2))), y3), 0)) -> c5(MARK(cons(s(from(first(cons(y0, y1), y2))), y3)))
   MARK(first(cons(s(from(from(y0))), y1), 0)) -> c5(MARK(cons(s(from(from(y0))), y1)))
   MARK(first(cons(s(from(from(first(y0, y1)))), y2), 0)) -> c5(MARK(cons(s(from(from(first(y0, y1)))), y2)))
   MARK(first(cons(s(from(from(from(y0)))), y1), 0)) -> c5(MARK(cons(s(from(from(from(y0)))), y1)))
   MARK(first(cons(s(from(from(s(y0)))), y1), 0)) -> c5(MARK(cons(s(from(from(s(y0)))), y1)))
   MARK(first(cons(s(from(from(cons(y0, y1)))), y2), 0)) -> c5(MARK(cons(s(from(from(cons(y0, y1)))), y2)))
   MARK(first(cons(s(from(from(0))), y0), 0)) -> c5(MARK(cons(s(from(from(0))), y0)))
   MARK(first(cons(s(from(from(nil))), y0), 0)) -> c5(MARK(cons(s(from(from(nil))), y0)))
K tuples:none
Defined Rule Symbols:   a__first_2, a__from_1, mark_1

Defined Pair Symbols:   MARK_1, A__FIRST_2, A__FROM_1

Compound Symbols:   c5_1, c6_1, c5_2, c6_2, c1_1, c3_1, c7_2, c7_1, c10_1, c11_1