Certification Problem

Input (TPDB SRS_Relative/Waldmann_19/random-39)

The rewrite relation of the following TRS is considered.

a(a(c(x1))) → a(c(c(x1))) (1)
b(b(c(x1))) → a(b(b(x1))) (2)
c(c(b(x1))) → a(c(a(x1))) (3)
b(a(c(x1))) → c(a(c(x1))) (4)
c(b(c(x1))) → b(b(b(x1))) (5)
b(b(a(x1))) → b(a(c(x1))) (6)

Property / Task

Prove or disprove termination.

Answer / Result

Yes.

Proof (by matchbox @ termCOMP 2023)

1 Split

We split R in the relative problem D/R-D and R-D, where the rules D

c(c(b(x1))) → a(c(a(x1))) (3)
are deleted.

1.1 Closure Under Flat Contexts

Using the flat contexts

{c(☐), b(☐), a(☐)}

We obtain the transformed TRS
c(c(c(b(x1)))) → c(a(c(a(x1)))) (7)
b(c(c(b(x1)))) → b(a(c(a(x1)))) (8)
a(c(c(b(x1)))) → a(a(c(a(x1)))) (9)
c(a(a(c(x1)))) → c(a(c(c(x1)))) (10)
c(b(b(c(x1)))) → c(a(b(b(x1)))) (11)
c(b(a(c(x1)))) → c(c(a(c(x1)))) (12)
c(c(b(c(x1)))) → c(b(b(b(x1)))) (13)
c(b(b(a(x1)))) → c(b(a(c(x1)))) (14)
b(a(a(c(x1)))) → b(a(c(c(x1)))) (15)
b(b(b(c(x1)))) → b(a(b(b(x1)))) (16)
b(b(a(c(x1)))) → b(c(a(c(x1)))) (17)
b(c(b(c(x1)))) → b(b(b(b(x1)))) (18)
b(b(b(a(x1)))) → b(b(a(c(x1)))) (19)
a(a(a(c(x1)))) → a(a(c(c(x1)))) (20)
a(b(b(c(x1)))) → a(a(b(b(x1)))) (21)
a(b(a(c(x1)))) → a(c(a(c(x1)))) (22)
a(c(b(c(x1)))) → a(b(b(b(x1)))) (23)
a(b(b(a(x1)))) → a(b(a(c(x1)))) (24)

1.1.1 Semantic Labeling

The following interpretations form a model of the rules.

As carrier we take the set {0,1,2}. Symbols are labeled by the interpretation of their arguments using the interpretations (modulo 3):

[c(x1)] = 3x1 + 0
[b(x1)] = 3x1 + 1
[a(x1)] = 3x1 + 2

We obtain the labeled TRS
a0(c0(c1(b2(x1)))) → a2(a0(c2(a2(x1)))) (25)
a0(c0(c1(b0(x1)))) → a2(a0(c2(a0(x1)))) (26)
a0(c0(c1(b1(x1)))) → a2(a0(c2(a1(x1)))) (27)
c0(c0(c1(b2(x1)))) → c2(a0(c2(a2(x1)))) (28)
c0(c0(c1(b0(x1)))) → c2(a0(c2(a0(x1)))) (29)
c0(c0(c1(b1(x1)))) → c2(a0(c2(a1(x1)))) (30)
b0(c0(c1(b2(x1)))) → b2(a0(c2(a2(x1)))) (31)
b0(c0(c1(b0(x1)))) → b2(a0(c2(a0(x1)))) (32)
b0(c0(c1(b1(x1)))) → b2(a0(c2(a1(x1)))) (33)
a2(a2(a0(c2(x1)))) → a2(a0(c0(c2(x1)))) (34)
a2(a2(a0(c0(x1)))) → a2(a0(c0(c0(x1)))) (35)
a2(a2(a0(c1(x1)))) → a2(a0(c0(c1(x1)))) (36)
c2(a2(a0(c2(x1)))) → c2(a0(c0(c2(x1)))) (37)
c2(a2(a0(c0(x1)))) → c2(a0(c0(c0(x1)))) (38)
c2(a2(a0(c1(x1)))) → c2(a0(c0(c1(x1)))) (39)
b2(a2(a0(c2(x1)))) → b2(a0(c0(c2(x1)))) (40)
b2(a2(a0(c0(x1)))) → b2(a0(c0(c0(x1)))) (41)
b2(a2(a0(c1(x1)))) → b2(a0(c0(c1(x1)))) (42)
a1(b1(b0(c2(x1)))) → a2(a1(b1(b2(x1)))) (43)
a1(b1(b0(c0(x1)))) → a2(a1(b1(b0(x1)))) (44)
a1(b1(b0(c1(x1)))) → a2(a1(b1(b1(x1)))) (45)
c1(b1(b0(c2(x1)))) → c2(a1(b1(b2(x1)))) (46)
c1(b1(b0(c0(x1)))) → c2(a1(b1(b0(x1)))) (47)
c1(b1(b0(c1(x1)))) → c2(a1(b1(b1(x1)))) (48)
b1(b1(b0(c2(x1)))) → b2(a1(b1(b2(x1)))) (49)
b1(b1(b0(c0(x1)))) → b2(a1(b1(b0(x1)))) (50)
b1(b1(b0(c1(x1)))) → b2(a1(b1(b1(x1)))) (51)
a1(b2(a0(c2(x1)))) → a0(c2(a0(c2(x1)))) (52)
a1(b2(a0(c0(x1)))) → a0(c2(a0(c0(x1)))) (53)
a1(b2(a0(c1(x1)))) → a0(c2(a0(c1(x1)))) (54)
c1(b2(a0(c2(x1)))) → c0(c2(a0(c2(x1)))) (55)
c1(b2(a0(c0(x1)))) → c0(c2(a0(c0(x1)))) (56)
c1(b2(a0(c1(x1)))) → c0(c2(a0(c1(x1)))) (57)
b1(b2(a0(c2(x1)))) → b0(c2(a0(c2(x1)))) (58)
b1(b2(a0(c0(x1)))) → b0(c2(a0(c0(x1)))) (59)
b1(b2(a0(c1(x1)))) → b0(c2(a0(c1(x1)))) (60)
a0(c1(b0(c2(x1)))) → a1(b1(b1(b2(x1)))) (61)
a0(c1(b0(c0(x1)))) → a1(b1(b1(b0(x1)))) (62)
a0(c1(b0(c1(x1)))) → a1(b1(b1(b1(x1)))) (63)
c0(c1(b0(c2(x1)))) → c1(b1(b1(b2(x1)))) (64)
c0(c1(b0(c0(x1)))) → c1(b1(b1(b0(x1)))) (65)
c0(c1(b0(c1(x1)))) → c1(b1(b1(b1(x1)))) (66)
b0(c1(b0(c2(x1)))) → b1(b1(b1(b2(x1)))) (67)
b0(c1(b0(c0(x1)))) → b1(b1(b1(b0(x1)))) (68)
b0(c1(b0(c1(x1)))) → b1(b1(b1(b1(x1)))) (69)
a1(b1(b2(a2(x1)))) → a1(b2(a0(c2(x1)))) (70)
a1(b1(b2(a0(x1)))) → a1(b2(a0(c0(x1)))) (71)
a1(b1(b2(a1(x1)))) → a1(b2(a0(c1(x1)))) (72)
c1(b1(b2(a2(x1)))) → c1(b2(a0(c2(x1)))) (73)
c1(b1(b2(a0(x1)))) → c1(b2(a0(c0(x1)))) (74)
c1(b1(b2(a1(x1)))) → c1(b2(a0(c1(x1)))) (75)
b1(b1(b2(a2(x1)))) → b1(b2(a0(c2(x1)))) (76)
b1(b1(b2(a0(x1)))) → b1(b2(a0(c0(x1)))) (77)
b1(b1(b2(a1(x1)))) → b1(b2(a0(c1(x1)))) (78)

1.1.1.1 Rule Removal

Using the matrix interpretations of dimension 1 with strict dimension 1 over the rationals with delta = 1
[c0(x1)] = x1 +
3/2
[c1(x1)] = x1 +
5/2
[c2(x1)] = x1 +
0
[b0(x1)] = x1 +
5/2
[b1(x1)] = x1 +
3/2
[b2(x1)] = x1 +
1
[a0(x1)] = x1 +
0
[a1(x1)] = x1 +
1
[a2(x1)] = x1 +
3/2
all of the following rules can be deleted.
a0(c0(c1(b2(x1)))) → a2(a0(c2(a2(x1)))) (25)
a0(c0(c1(b0(x1)))) → a2(a0(c2(a0(x1)))) (26)
a0(c0(c1(b1(x1)))) → a2(a0(c2(a1(x1)))) (27)
c0(c0(c1(b2(x1)))) → c2(a0(c2(a2(x1)))) (28)
c0(c0(c1(b0(x1)))) → c2(a0(c2(a0(x1)))) (29)
c0(c0(c1(b1(x1)))) → c2(a0(c2(a1(x1)))) (30)
b0(c0(c1(b2(x1)))) → b2(a0(c2(a2(x1)))) (31)
b0(c0(c1(b0(x1)))) → b2(a0(c2(a0(x1)))) (32)
b0(c0(c1(b1(x1)))) → b2(a0(c2(a1(x1)))) (33)
a1(b1(b0(c1(x1)))) → a2(a1(b1(b1(x1)))) (45)
c1(b1(b0(c2(x1)))) → c2(a1(b1(b2(x1)))) (46)
c1(b1(b0(c0(x1)))) → c2(a1(b1(b0(x1)))) (47)
c1(b1(b0(c1(x1)))) → c2(a1(b1(b1(x1)))) (48)
b1(b1(b0(c2(x1)))) → b2(a1(b1(b2(x1)))) (49)
b1(b1(b0(c0(x1)))) → b2(a1(b1(b0(x1)))) (50)
b1(b1(b0(c1(x1)))) → b2(a1(b1(b1(x1)))) (51)
a1(b2(a0(c2(x1)))) → a0(c2(a0(c2(x1)))) (52)
a1(b2(a0(c0(x1)))) → a0(c2(a0(c0(x1)))) (53)
a1(b2(a0(c1(x1)))) → a0(c2(a0(c1(x1)))) (54)
c1(b2(a0(c2(x1)))) → c0(c2(a0(c2(x1)))) (55)
c1(b2(a0(c0(x1)))) → c0(c2(a0(c0(x1)))) (56)
c1(b2(a0(c1(x1)))) → c0(c2(a0(c1(x1)))) (57)
a0(c1(b0(c1(x1)))) → a1(b1(b1(b1(x1)))) (63)
c0(c1(b0(c1(x1)))) → c1(b1(b1(b1(x1)))) (66)
b0(c1(b0(c2(x1)))) → b1(b1(b1(b2(x1)))) (67)
b0(c1(b0(c0(x1)))) → b1(b1(b1(b0(x1)))) (68)
b0(c1(b0(c1(x1)))) → b1(b1(b1(b1(x1)))) (69)
a1(b1(b2(a2(x1)))) → a1(b2(a0(c2(x1)))) (70)
c1(b1(b2(a2(x1)))) → c1(b2(a0(c2(x1)))) (73)
b1(b1(b2(a2(x1)))) → b1(b2(a0(c2(x1)))) (76)

1.1.1.1.1 R is empty

There are no rules in the TRS. Hence, it is terminating.

1.2 Split

We split R in the relative problem D/R-D and R-D, where the rules D

b(b(a(x1))) → b(a(c(x1))) (6)
are deleted.

1.2.1 Closure Under Flat Contexts

Using the flat contexts

{c(☐), b(☐), a(☐)}

We obtain the transformed TRS
c(b(b(a(x1)))) → c(b(a(c(x1)))) (14)
b(b(b(a(x1)))) → b(b(a(c(x1)))) (19)
a(b(b(a(x1)))) → a(b(a(c(x1)))) (24)
c(a(a(c(x1)))) → c(a(c(c(x1)))) (10)
c(b(b(c(x1)))) → c(a(b(b(x1)))) (11)
c(b(a(c(x1)))) → c(c(a(c(x1)))) (12)
c(c(b(c(x1)))) → c(b(b(b(x1)))) (13)
b(a(a(c(x1)))) → b(a(c(c(x1)))) (15)
b(b(b(c(x1)))) → b(a(b(b(x1)))) (16)
b(b(a(c(x1)))) → b(c(a(c(x1)))) (17)
b(c(b(c(x1)))) → b(b(b(b(x1)))) (18)
a(a(a(c(x1)))) → a(a(c(c(x1)))) (20)
a(b(b(c(x1)))) → a(a(b(b(x1)))) (21)
a(b(a(c(x1)))) → a(c(a(c(x1)))) (22)
a(c(b(c(x1)))) → a(b(b(b(x1)))) (23)

1.2.1.1 Semantic Labeling

The following interpretations form a model of the rules.

As carrier we take the set {0,1,2}. Symbols are labeled by the interpretation of their arguments using the interpretations (modulo 3):

[c(x1)] = 3x1 + 0
[b(x1)] = 3x1 + 1
[a(x1)] = 3x1 + 2

We obtain the labeled TRS
a1(b1(b2(a2(x1)))) → a1(b2(a0(c2(x1)))) (70)
a1(b1(b2(a0(x1)))) → a1(b2(a0(c0(x1)))) (71)
a1(b1(b2(a1(x1)))) → a1(b2(a0(c1(x1)))) (72)
c1(b1(b2(a2(x1)))) → c1(b2(a0(c2(x1)))) (73)
c1(b1(b2(a0(x1)))) → c1(b2(a0(c0(x1)))) (74)
c1(b1(b2(a1(x1)))) → c1(b2(a0(c1(x1)))) (75)
b1(b1(b2(a2(x1)))) → b1(b2(a0(c2(x1)))) (76)
b1(b1(b2(a0(x1)))) → b1(b2(a0(c0(x1)))) (77)
b1(b1(b2(a1(x1)))) → b1(b2(a0(c1(x1)))) (78)
a2(a2(a0(c2(x1)))) → a2(a0(c0(c2(x1)))) (34)
a2(a2(a0(c0(x1)))) → a2(a0(c0(c0(x1)))) (35)
a2(a2(a0(c1(x1)))) → a2(a0(c0(c1(x1)))) (36)
c2(a2(a0(c2(x1)))) → c2(a0(c0(c2(x1)))) (37)
c2(a2(a0(c0(x1)))) → c2(a0(c0(c0(x1)))) (38)
c2(a2(a0(c1(x1)))) → c2(a0(c0(c1(x1)))) (39)
b2(a2(a0(c2(x1)))) → b2(a0(c0(c2(x1)))) (40)
b2(a2(a0(c0(x1)))) → b2(a0(c0(c0(x1)))) (41)
b2(a2(a0(c1(x1)))) → b2(a0(c0(c1(x1)))) (42)
a1(b1(b0(c2(x1)))) → a2(a1(b1(b2(x1)))) (43)
a1(b1(b0(c0(x1)))) → a2(a1(b1(b0(x1)))) (44)
a1(b1(b0(c1(x1)))) → a2(a1(b1(b1(x1)))) (45)
c1(b1(b0(c2(x1)))) → c2(a1(b1(b2(x1)))) (46)
c1(b1(b0(c0(x1)))) → c2(a1(b1(b0(x1)))) (47)
c1(b1(b0(c1(x1)))) → c2(a1(b1(b1(x1)))) (48)
b1(b1(b0(c2(x1)))) → b2(a1(b1(b2(x1)))) (49)
b1(b1(b0(c0(x1)))) → b2(a1(b1(b0(x1)))) (50)
b1(b1(b0(c1(x1)))) → b2(a1(b1(b1(x1)))) (51)
a1(b2(a0(c2(x1)))) → a0(c2(a0(c2(x1)))) (52)
a1(b2(a0(c0(x1)))) → a0(c2(a0(c0(x1)))) (53)
a1(b2(a0(c1(x1)))) → a0(c2(a0(c1(x1)))) (54)
c1(b2(a0(c2(x1)))) → c0(c2(a0(c2(x1)))) (55)
c1(b2(a0(c0(x1)))) → c0(c2(a0(c0(x1)))) (56)
c1(b2(a0(c1(x1)))) → c0(c2(a0(c1(x1)))) (57)
b1(b2(a0(c2(x1)))) → b0(c2(a0(c2(x1)))) (58)
b1(b2(a0(c0(x1)))) → b0(c2(a0(c0(x1)))) (59)
b1(b2(a0(c1(x1)))) → b0(c2(a0(c1(x1)))) (60)
a0(c1(b0(c2(x1)))) → a1(b1(b1(b2(x1)))) (61)
a0(c1(b0(c0(x1)))) → a1(b1(b1(b0(x1)))) (62)
a0(c1(b0(c1(x1)))) → a1(b1(b1(b1(x1)))) (63)
c0(c1(b0(c2(x1)))) → c1(b1(b1(b2(x1)))) (64)
c0(c1(b0(c0(x1)))) → c1(b1(b1(b0(x1)))) (65)
c0(c1(b0(c1(x1)))) → c1(b1(b1(b1(x1)))) (66)
b0(c1(b0(c2(x1)))) → b1(b1(b1(b2(x1)))) (67)
b0(c1(b0(c0(x1)))) → b1(b1(b1(b0(x1)))) (68)
b0(c1(b0(c1(x1)))) → b1(b1(b1(b1(x1)))) (69)

1.2.1.1.1 Rule Removal

Using the matrix interpretations of dimension 1 with strict dimension 1 over the rationals with delta = 1
[c0(x1)] = x1 +
5/2
[c1(x1)] = x1 +
4
[c2(x1)] = x1 +
1
[b0(x1)] = x1 +
3
[b1(x1)] = x1 +
5/2
[b2(x1)] = x1 +
3/2
[a0(x1)] = x1 +
0
[a1(x1)] = x1 +
3/2
[a2(x1)] = x1 +
5/2
all of the following rules can be deleted.
a1(b1(b2(a2(x1)))) → a1(b2(a0(c2(x1)))) (70)
c1(b1(b2(a2(x1)))) → c1(b2(a0(c2(x1)))) (73)
b1(b1(b2(a2(x1)))) → b1(b2(a0(c2(x1)))) (76)
a1(b1(b0(c1(x1)))) → a2(a1(b1(b1(x1)))) (45)
c1(b1(b0(c2(x1)))) → c2(a1(b1(b2(x1)))) (46)
c1(b1(b0(c0(x1)))) → c2(a1(b1(b0(x1)))) (47)
c1(b1(b0(c1(x1)))) → c2(a1(b1(b1(x1)))) (48)
b1(b1(b0(c2(x1)))) → b2(a1(b1(b2(x1)))) (49)
b1(b1(b0(c0(x1)))) → b2(a1(b1(b0(x1)))) (50)
b1(b1(b0(c1(x1)))) → b2(a1(b1(b1(x1)))) (51)
a1(b2(a0(c2(x1)))) → a0(c2(a0(c2(x1)))) (52)
a1(b2(a0(c0(x1)))) → a0(c2(a0(c0(x1)))) (53)
a1(b2(a0(c1(x1)))) → a0(c2(a0(c1(x1)))) (54)
c1(b2(a0(c2(x1)))) → c0(c2(a0(c2(x1)))) (55)
c1(b2(a0(c0(x1)))) → c0(c2(a0(c0(x1)))) (56)
c1(b2(a0(c1(x1)))) → c0(c2(a0(c1(x1)))) (57)
a0(c1(b0(c1(x1)))) → a1(b1(b1(b1(x1)))) (63)
c0(c1(b0(c1(x1)))) → c1(b1(b1(b1(x1)))) (66)
b0(c1(b0(c2(x1)))) → b1(b1(b1(b2(x1)))) (67)
b0(c1(b0(c0(x1)))) → b1(b1(b1(b0(x1)))) (68)
b0(c1(b0(c1(x1)))) → b1(b1(b1(b1(x1)))) (69)

1.2.1.1.1.1 String Reversal

Since only unary symbols occur, one can reverse all terms and obtains the TRS
a0(b2(b1(a1(x1)))) → c0(a0(b2(a1(x1)))) (79)
a1(b2(b1(a1(x1)))) → c1(a0(b2(a1(x1)))) (80)
a0(b2(b1(c1(x1)))) → c0(a0(b2(c1(x1)))) (81)
a1(b2(b1(c1(x1)))) → c1(a0(b2(c1(x1)))) (82)
a0(b2(b1(b1(x1)))) → c0(a0(b2(b1(x1)))) (83)
a1(b2(b1(b1(x1)))) → c1(a0(b2(b1(x1)))) (84)
c2(a0(a2(a2(x1)))) → c2(c0(a0(a2(x1)))) (85)
c0(a0(a2(a2(x1)))) → c0(c0(a0(a2(x1)))) (86)
c1(a0(a2(a2(x1)))) → c1(c0(a0(a2(x1)))) (87)
c2(a0(a2(c2(x1)))) → c2(c0(a0(c2(x1)))) (88)
c0(a0(a2(c2(x1)))) → c0(c0(a0(c2(x1)))) (89)
c1(a0(a2(c2(x1)))) → c1(c0(a0(c2(x1)))) (90)
c2(a0(a2(b2(x1)))) → c2(c0(a0(b2(x1)))) (91)
c0(a0(a2(b2(x1)))) → c0(c0(a0(b2(x1)))) (92)
c1(a0(a2(b2(x1)))) → c1(c0(a0(b2(x1)))) (93)
c2(b0(b1(a1(x1)))) → b2(b1(a1(a2(x1)))) (94)
c0(b0(b1(a1(x1)))) → b0(b1(a1(a2(x1)))) (95)
c2(a0(b2(b1(x1)))) → c2(a0(c2(b0(x1)))) (96)
c0(a0(b2(b1(x1)))) → c0(a0(c2(b0(x1)))) (97)
c1(a0(b2(b1(x1)))) → c1(a0(c2(b0(x1)))) (98)
c2(b0(c1(a0(x1)))) → b2(b1(b1(a1(x1)))) (99)
c0(b0(c1(a0(x1)))) → b0(b1(b1(a1(x1)))) (100)
c2(b0(c1(c0(x1)))) → b2(b1(b1(c1(x1)))) (101)
c0(b0(c1(c0(x1)))) → b0(b1(b1(c1(x1)))) (102)

1.2.1.1.1.1.1 Rule Removal

Using the matrix interpretations of dimension 1 with strict dimension 1 over the naturals
[c0(x1)] =
2
· x1 +
1
[c1(x1)] =
1
· x1 +
0
[c2(x1)] =
2
· x1 +
0
[b0(x1)] =
2
· x1 +
1
[b1(x1)] =
2
· x1 +
1
[b2(x1)] =
2
· x1 +
0
[a0(x1)] =
2
· x1 +
1
[a1(x1)] =
1
· x1 +
0
[a2(x1)] =
2
· x1 +
1
all of the following rules can be deleted.
a0(b2(b1(a1(x1)))) → c0(a0(b2(a1(x1)))) (79)
a1(b2(b1(a1(x1)))) → c1(a0(b2(a1(x1)))) (80)
a0(b2(b1(c1(x1)))) → c0(a0(b2(c1(x1)))) (81)
a1(b2(b1(c1(x1)))) → c1(a0(b2(c1(x1)))) (82)
a0(b2(b1(b1(x1)))) → c0(a0(b2(b1(x1)))) (83)
a1(b2(b1(b1(x1)))) → c1(a0(b2(b1(x1)))) (84)

1.2.1.1.1.1.1.1 Rule Removal

Using the matrix interpretations of dimension 1 with strict dimension 1 over the rationals with delta = 1
[c0(x1)] = x1 +
0
[c1(x1)] = x1 +
1
[c2(x1)] = x1 +
0
[b0(x1)] = x1 +
0
[b1(x1)] = x1 +
0
[b2(x1)] = x1 +
0
[a0(x1)] = x1 +
1
[a1(x1)] = x1 +
0
[a2(x1)] = x1 +
0
all of the following rules can be deleted.
c2(b0(c1(a0(x1)))) → b2(b1(b1(a1(x1)))) (99)
c0(b0(c1(a0(x1)))) → b0(b1(b1(a1(x1)))) (100)

1.2.1.1.1.1.1.1.1 String Reversal

Since only unary symbols occur, one can reverse all terms and obtains the TRS
a2(a2(a0(c2(x1)))) → a2(a0(c0(c2(x1)))) (34)
a2(a2(a0(c0(x1)))) → a2(a0(c0(c0(x1)))) (35)
a2(a2(a0(c1(x1)))) → a2(a0(c0(c1(x1)))) (36)
c2(a2(a0(c2(x1)))) → c2(a0(c0(c2(x1)))) (37)
c2(a2(a0(c0(x1)))) → c2(a0(c0(c0(x1)))) (38)
c2(a2(a0(c1(x1)))) → c2(a0(c0(c1(x1)))) (39)
b2(a2(a0(c2(x1)))) → b2(a0(c0(c2(x1)))) (40)
b2(a2(a0(c0(x1)))) → b2(a0(c0(c0(x1)))) (41)
b2(a2(a0(c1(x1)))) → b2(a0(c0(c1(x1)))) (42)
a1(b1(b0(c2(x1)))) → a2(a1(b1(b2(x1)))) (43)
a1(b1(b0(c0(x1)))) → a2(a1(b1(b0(x1)))) (44)
b1(b2(a0(c2(x1)))) → b0(c2(a0(c2(x1)))) (58)
b1(b2(a0(c0(x1)))) → b0(c2(a0(c0(x1)))) (59)
b1(b2(a0(c1(x1)))) → b0(c2(a0(c1(x1)))) (60)
c0(c1(b0(c2(x1)))) → c1(b1(b1(b2(x1)))) (64)
c0(c1(b0(c0(x1)))) → c1(b1(b1(b0(x1)))) (65)

1.2.1.1.1.1.1.1.1.1 R is empty

There are no rules in the TRS. Hence, it is terminating.

1.2.2 Closure Under Flat Contexts

Using the flat contexts

{c(☐), b(☐), a(☐)}

We obtain the transformed TRS
c(a(a(c(x1)))) → c(a(c(c(x1)))) (10)
c(b(b(c(x1)))) → c(a(b(b(x1)))) (11)
c(b(a(c(x1)))) → c(c(a(c(x1)))) (12)
c(c(b(c(x1)))) → c(b(b(b(x1)))) (13)
b(a(a(c(x1)))) → b(a(c(c(x1)))) (15)
b(b(b(c(x1)))) → b(a(b(b(x1)))) (16)
b(b(a(c(x1)))) → b(c(a(c(x1)))) (17)
b(c(b(c(x1)))) → b(b(b(b(x1)))) (18)
a(a(a(c(x1)))) → a(a(c(c(x1)))) (20)
a(b(b(c(x1)))) → a(a(b(b(x1)))) (21)
a(b(a(c(x1)))) → a(c(a(c(x1)))) (22)
a(c(b(c(x1)))) → a(b(b(b(x1)))) (23)

1.2.2.1 Semantic Labeling

The following interpretations form a model of the rules.

As carrier we take the set {0,1,2}. Symbols are labeled by the interpretation of their arguments using the interpretations (modulo 3):

[c(x1)] = 3x1 + 0
[b(x1)] = 3x1 + 1
[a(x1)] = 3x1 + 2

We obtain the labeled TRS
a2(a2(a0(c2(x1)))) → a2(a0(c0(c2(x1)))) (34)
a2(a2(a0(c0(x1)))) → a2(a0(c0(c0(x1)))) (35)
a2(a2(a0(c1(x1)))) → a2(a0(c0(c1(x1)))) (36)
c2(a2(a0(c2(x1)))) → c2(a0(c0(c2(x1)))) (37)
c2(a2(a0(c0(x1)))) → c2(a0(c0(c0(x1)))) (38)
c2(a2(a0(c1(x1)))) → c2(a0(c0(c1(x1)))) (39)
b2(a2(a0(c2(x1)))) → b2(a0(c0(c2(x1)))) (40)
b2(a2(a0(c0(x1)))) → b2(a0(c0(c0(x1)))) (41)
b2(a2(a0(c1(x1)))) → b2(a0(c0(c1(x1)))) (42)
a1(b1(b0(c2(x1)))) → a2(a1(b1(b2(x1)))) (43)
a1(b1(b0(c0(x1)))) → a2(a1(b1(b0(x1)))) (44)
a1(b1(b0(c1(x1)))) → a2(a1(b1(b1(x1)))) (45)
c1(b1(b0(c2(x1)))) → c2(a1(b1(b2(x1)))) (46)
c1(b1(b0(c0(x1)))) → c2(a1(b1(b0(x1)))) (47)
c1(b1(b0(c1(x1)))) → c2(a1(b1(b1(x1)))) (48)
b1(b1(b0(c2(x1)))) → b2(a1(b1(b2(x1)))) (49)
b1(b1(b0(c0(x1)))) → b2(a1(b1(b0(x1)))) (50)
b1(b1(b0(c1(x1)))) → b2(a1(b1(b1(x1)))) (51)
a1(b2(a0(c2(x1)))) → a0(c2(a0(c2(x1)))) (52)
a1(b2(a0(c0(x1)))) → a0(c2(a0(c0(x1)))) (53)
a1(b2(a0(c1(x1)))) → a0(c2(a0(c1(x1)))) (54)
c1(b2(a0(c2(x1)))) → c0(c2(a0(c2(x1)))) (55)
c1(b2(a0(c0(x1)))) → c0(c2(a0(c0(x1)))) (56)
c1(b2(a0(c1(x1)))) → c0(c2(a0(c1(x1)))) (57)
b1(b2(a0(c2(x1)))) → b0(c2(a0(c2(x1)))) (58)
b1(b2(a0(c0(x1)))) → b0(c2(a0(c0(x1)))) (59)
b1(b2(a0(c1(x1)))) → b0(c2(a0(c1(x1)))) (60)
a0(c1(b0(c2(x1)))) → a1(b1(b1(b2(x1)))) (61)
a0(c1(b0(c0(x1)))) → a1(b1(b1(b0(x1)))) (62)
a0(c1(b0(c1(x1)))) → a1(b1(b1(b1(x1)))) (63)
c0(c1(b0(c2(x1)))) → c1(b1(b1(b2(x1)))) (64)
c0(c1(b0(c0(x1)))) → c1(b1(b1(b0(x1)))) (65)
c0(c1(b0(c1(x1)))) → c1(b1(b1(b1(x1)))) (66)
b0(c1(b0(c2(x1)))) → b1(b1(b1(b2(x1)))) (67)
b0(c1(b0(c0(x1)))) → b1(b1(b1(b0(x1)))) (68)
b0(c1(b0(c1(x1)))) → b1(b1(b1(b1(x1)))) (69)

1.2.2.1.1 Rule Removal

Using the matrix interpretations of dimension 1 with strict dimension 1 over the rationals with delta = 1
[c0(x1)] = x1 +
1
[c1(x1)] = x1 +
4
[c2(x1)] = x1 +
0
[b0(x1)] = x1 +
1
[b1(x1)] = x1 +
1
[b2(x1)] = x1 +
0
[a0(x1)] = x1 +
0
[a1(x1)] = x1 +
1
[a2(x1)] = x1 +
1
all of the following rules can be deleted.
a1(b1(b0(c1(x1)))) → a2(a1(b1(b1(x1)))) (45)
c1(b1(b0(c2(x1)))) → c2(a1(b1(b2(x1)))) (46)
c1(b1(b0(c0(x1)))) → c2(a1(b1(b0(x1)))) (47)
c1(b1(b0(c1(x1)))) → c2(a1(b1(b1(x1)))) (48)
b1(b1(b0(c2(x1)))) → b2(a1(b1(b2(x1)))) (49)
b1(b1(b0(c0(x1)))) → b2(a1(b1(b0(x1)))) (50)
b1(b1(b0(c1(x1)))) → b2(a1(b1(b1(x1)))) (51)
a1(b2(a0(c2(x1)))) → a0(c2(a0(c2(x1)))) (52)
a1(b2(a0(c0(x1)))) → a0(c2(a0(c0(x1)))) (53)
a1(b2(a0(c1(x1)))) → a0(c2(a0(c1(x1)))) (54)
c1(b2(a0(c2(x1)))) → c0(c2(a0(c2(x1)))) (55)
c1(b2(a0(c0(x1)))) → c0(c2(a0(c0(x1)))) (56)
c1(b2(a0(c1(x1)))) → c0(c2(a0(c1(x1)))) (57)
a0(c1(b0(c2(x1)))) → a1(b1(b1(b2(x1)))) (61)
a0(c1(b0(c0(x1)))) → a1(b1(b1(b0(x1)))) (62)
a0(c1(b0(c1(x1)))) → a1(b1(b1(b1(x1)))) (63)
c0(c1(b0(c1(x1)))) → c1(b1(b1(b1(x1)))) (66)
b0(c1(b0(c2(x1)))) → b1(b1(b1(b2(x1)))) (67)
b0(c1(b0(c0(x1)))) → b1(b1(b1(b0(x1)))) (68)
b0(c1(b0(c1(x1)))) → b1(b1(b1(b1(x1)))) (69)

1.2.2.1.1.1 Rule Removal

Using the matrix interpretations of dimension 1 with strict dimension 1 over the naturals
[c0(x1)] =
2
· x1 +
1
[c1(x1)] =
2
· x1 +
1
[c2(x1)] =
2
· x1 +
1
[b0(x1)] =
2
· x1 +
1
[b1(x1)] =
2
· x1 +
1
[b2(x1)] =
2
· x1 +
1
[a0(x1)] =
2
· x1 +
1
[a1(x1)] =
2
· x1 +
0
[a2(x1)] =
2
· x1 +
1
all of the following rules can be deleted.
a1(b1(b0(c2(x1)))) → a2(a1(b1(b2(x1)))) (43)
a1(b1(b0(c0(x1)))) → a2(a1(b1(b0(x1)))) (44)

1.2.2.1.1.1.1 Rule Removal

Using the matrix interpretations of dimension 1 with strict dimension 1 over the rationals with delta = 1
[c0(x1)] = x1 +
4
[c1(x1)] = x1 +
0
[c2(x1)] = x1 +
0
[b0(x1)] = x1 +
0
[b1(x1)] = x1 +
1
[b2(x1)] = x1 +
1
[a0(x1)] = x1 +
0
[a2(x1)] = x1 +
5
all of the following rules can be deleted.
a2(a2(a0(c2(x1)))) → a2(a0(c0(c2(x1)))) (34)
a2(a2(a0(c0(x1)))) → a2(a0(c0(c0(x1)))) (35)
a2(a2(a0(c1(x1)))) → a2(a0(c0(c1(x1)))) (36)
c2(a2(a0(c2(x1)))) → c2(a0(c0(c2(x1)))) (37)
c2(a2(a0(c0(x1)))) → c2(a0(c0(c0(x1)))) (38)
c2(a2(a0(c1(x1)))) → c2(a0(c0(c1(x1)))) (39)
b2(a2(a0(c2(x1)))) → b2(a0(c0(c2(x1)))) (40)
b2(a2(a0(c0(x1)))) → b2(a0(c0(c0(x1)))) (41)
b2(a2(a0(c1(x1)))) → b2(a0(c0(c1(x1)))) (42)
b1(b2(a0(c2(x1)))) → b0(c2(a0(c2(x1)))) (58)
b1(b2(a0(c0(x1)))) → b0(c2(a0(c0(x1)))) (59)
b1(b2(a0(c1(x1)))) → b0(c2(a0(c1(x1)))) (60)
c0(c1(b0(c2(x1)))) → c1(b1(b1(b2(x1)))) (64)
c0(c1(b0(c0(x1)))) → c1(b1(b1(b0(x1)))) (65)

1.2.2.1.1.1.1.1 R is empty

There are no rules in the TRS. Hence, it is terminating.