Certification Problem

Input (TPDB SRS_Relative/Mixed_relative_SRS/dup04)

The relative rewrite relation R/S is considered where R is the following TRS

a(a(b(b(a(a(x1)))))) a(a(b(b(b(b(a(a(x1)))))))) (1)
b(b(a(a(b(b(x1)))))) b(b(a(a(a(a(b(b(x1)))))))) (2)

and S is the following TRS.

a(a(x1)) a(a(a(a(a(a(x1)))))) (3)
b(b(x1)) b(b(b(b(b(b(x1)))))) (4)

Property / Task

Prove or disprove termination.

Answer / Result

Yes.

Proof (by matchbox @ termCOMP 2023)

1 Rule Removal

Using the matrix interpretations of dimension 4 with strict dimension 1 over the naturals
[b(x1)] =
1 0 0 1
0 0 0 1
0 1 0 0
0 0 0 0
· x1 +
0
1
0
0
[a(x1)] =
1 0 1 0
0 0 3 0
0 0 0 0
0 1 2 0
· x1 +
0
0
0
0
all of the following rules can be deleted.
b(b(a(a(b(b(x1)))))) b(b(a(a(a(a(b(b(x1)))))))) (2)

1.1 Closure Under Flat Contexts

Using the flat contexts

{b(), a()}

We obtain the transformed TRS
b(a(a(b(b(a(a(x1))))))) b(a(a(b(b(b(b(a(a(x1))))))))) (5)
a(a(a(b(b(a(a(x1))))))) a(a(a(b(b(b(b(a(a(x1))))))))) (6)
b(a(a(x1))) b(a(a(a(a(a(a(x1))))))) (7)
b(b(b(x1))) b(b(b(b(b(b(b(x1))))))) (8)
a(a(a(x1))) a(a(a(a(a(a(a(x1))))))) (9)
a(b(b(x1))) a(b(b(b(b(b(b(x1))))))) (10)

1.1.1 Closure Under Flat Contexts

Using the flat contexts

{b(), a()}

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

1.1.1.1 Closure Under Flat Contexts

Using the flat contexts

{b(), a()}

We obtain the transformed TRS
b(b(b(a(a(b(b(a(a(x1))))))))) b(b(b(a(a(b(b(b(b(a(a(x1))))))))))) (23)
b(b(a(a(a(b(b(a(a(x1))))))))) b(b(a(a(a(b(b(b(b(a(a(x1))))))))))) (24)
b(a(b(a(a(b(b(a(a(x1))))))))) b(a(b(a(a(b(b(b(b(a(a(x1))))))))))) (25)
b(a(a(a(a(b(b(a(a(x1))))))))) b(a(a(a(a(b(b(b(b(a(a(x1))))))))))) (26)
a(b(b(a(a(b(b(a(a(x1))))))))) a(b(b(a(a(b(b(b(b(a(a(x1))))))))))) (27)
a(b(a(a(a(b(b(a(a(x1))))))))) a(b(a(a(a(b(b(b(b(a(a(x1))))))))))) (28)
a(a(b(a(a(b(b(a(a(x1))))))))) a(a(b(a(a(b(b(b(b(a(a(x1))))))))))) (29)
a(a(a(a(a(b(b(a(a(x1))))))))) a(a(a(a(a(b(b(b(b(a(a(x1))))))))))) (30)
b(b(b(a(a(x1))))) b(b(b(a(a(a(a(a(a(x1))))))))) (31)
b(b(b(b(b(x1))))) b(b(b(b(b(b(b(b(b(x1))))))))) (32)
b(b(a(a(a(x1))))) b(b(a(a(a(a(a(a(a(x1))))))))) (33)
b(b(a(b(b(x1))))) b(b(a(b(b(b(b(b(b(x1))))))))) (34)
b(a(b(a(a(x1))))) b(a(b(a(a(a(a(a(a(x1))))))))) (35)
b(a(b(b(b(x1))))) b(a(b(b(b(b(b(b(b(x1))))))))) (36)
b(a(a(a(a(x1))))) b(a(a(a(a(a(a(a(a(x1))))))))) (37)
b(a(a(b(b(x1))))) b(a(a(b(b(b(b(b(b(x1))))))))) (38)
a(b(b(a(a(x1))))) a(b(b(a(a(a(a(a(a(x1))))))))) (39)
a(b(b(b(b(x1))))) a(b(b(b(b(b(b(b(b(x1))))))))) (40)
a(b(a(a(a(x1))))) a(b(a(a(a(a(a(a(a(x1))))))))) (41)
a(b(a(b(b(x1))))) a(b(a(b(b(b(b(b(b(x1))))))))) (42)
a(a(b(a(a(x1))))) a(a(b(a(a(a(a(a(a(x1))))))))) (43)
a(a(b(b(b(x1))))) a(a(b(b(b(b(b(b(b(x1))))))))) (44)
a(a(a(a(a(x1))))) a(a(a(a(a(a(a(a(a(x1))))))))) (45)
a(a(a(b(b(x1))))) a(a(a(b(b(b(b(b(b(x1))))))))) (46)

1.1.1.1.1 Semantic Labeling

The following interpretations form a model of the rules.

As carrier we take the set {0,...,7}. Symbols are labeled by the interpretation of their arguments using the interpretations (modulo 8):

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

We obtain the labeled TRS

There are 192 ruless (increase limit for explicit display).

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
[b0(x1)] = x1 +
0
[b4(x1)] = x1 +
0
[b2(x1)] = x1 +
0
[b6(x1)] = x1 +
0
[b1(x1)] = x1 +
0
[b5(x1)] = x1 +
0
[b3(x1)] = x1 +
1
[b7(x1)] = x1 +
0
[a0(x1)] = x1 +
0
[a4(x1)] = x1 +
1
[a2(x1)] = x1 +
0
[a6(x1)] = x1 +
0
[a1(x1)] = x1 +
0
[a5(x1)] = x1 +
0
[a3(x1)] = x1 +
0
[a7(x1)] = x1 +
0
all of the following rules can be deleted.
a7(a7(a3(a1(a4(b6(b7(a7(a7(x1))))))))) a7(a7(a3(a1(a0(b0(b4(b6(b7(a7(a7(x1))))))))))) (47)
a7(a7(a3(a1(a4(b6(b7(a7(a3(x1))))))))) a7(a7(a3(a1(a0(b0(b4(b6(b7(a7(a3(x1))))))))))) (48)
a7(a7(a3(a1(a4(b6(b7(a3(a5(x1))))))))) a7(a7(a3(a1(a0(b0(b4(b6(b7(a3(a5(x1))))))))))) (49)
a7(a7(a3(a1(a4(b6(b7(a3(a1(x1))))))))) a7(a7(a3(a1(a0(b0(b4(b6(b7(a3(a1(x1))))))))))) (50)
a7(a7(a3(a1(a4(b6(b3(a5(a6(x1))))))))) a7(a7(a3(a1(a0(b0(b4(b6(b3(a5(a6(x1))))))))))) (51)
a7(a7(a3(a1(a4(b6(b3(a5(a2(x1))))))))) a7(a7(a3(a1(a0(b0(b4(b6(b3(a5(a2(x1))))))))))) (52)
a7(a7(a3(a1(a4(b6(b3(a1(a4(x1))))))))) a7(a7(a3(a1(a0(b0(b4(b6(b3(a1(a4(x1))))))))))) (53)
a7(a7(a3(a1(a4(b6(b3(a1(a0(x1))))))))) a7(a7(a3(a1(a0(b0(b4(b6(b3(a1(a0(x1))))))))))) (54)
a5(a6(b3(a1(a4(b6(b7(a7(a7(x1))))))))) a5(a6(b3(a1(a0(b0(b4(b6(b7(a7(a7(x1))))))))))) (55)
a5(a6(b3(a1(a4(b6(b7(a7(a3(x1))))))))) a5(a6(b3(a1(a0(b0(b4(b6(b7(a7(a3(x1))))))))))) (56)
a5(a6(b3(a1(a4(b6(b7(a3(a5(x1))))))))) a5(a6(b3(a1(a0(b0(b4(b6(b7(a3(a5(x1))))))))))) (57)
a5(a6(b3(a1(a4(b6(b7(a3(a1(x1))))))))) a5(a6(b3(a1(a0(b0(b4(b6(b7(a3(a1(x1))))))))))) (58)
a5(a6(b3(a1(a4(b6(b3(a5(a6(x1))))))))) a5(a6(b3(a1(a0(b0(b4(b6(b3(a5(a6(x1))))))))))) (59)
a5(a6(b3(a1(a4(b6(b3(a5(a2(x1))))))))) a5(a6(b3(a1(a0(b0(b4(b6(b3(a5(a2(x1))))))))))) (60)
a5(a6(b3(a1(a4(b6(b3(a1(a4(x1))))))))) a5(a6(b3(a1(a0(b0(b4(b6(b3(a1(a4(x1))))))))))) (61)
a5(a6(b3(a1(a4(b6(b3(a1(a0(x1))))))))) a5(a6(b3(a1(a0(b0(b4(b6(b3(a1(a0(x1))))))))))) (62)
a6(b7(a3(a1(a4(b6(b7(a7(a7(x1))))))))) a6(b7(a3(a1(a0(b0(b4(b6(b7(a7(a7(x1))))))))))) (63)
a6(b7(a3(a1(a4(b6(b7(a7(a3(x1))))))))) a6(b7(a3(a1(a0(b0(b4(b6(b7(a7(a3(x1))))))))))) (64)
a6(b7(a3(a1(a4(b6(b7(a3(a5(x1))))))))) a6(b7(a3(a1(a0(b0(b4(b6(b7(a3(a5(x1))))))))))) (65)
a6(b7(a3(a1(a4(b6(b7(a3(a1(x1))))))))) a6(b7(a3(a1(a0(b0(b4(b6(b7(a3(a1(x1))))))))))) (66)
a6(b7(a3(a1(a4(b6(b3(a5(a6(x1))))))))) a6(b7(a3(a1(a0(b0(b4(b6(b3(a5(a6(x1))))))))))) (67)
a6(b7(a3(a1(a4(b6(b3(a5(a2(x1))))))))) a6(b7(a3(a1(a0(b0(b4(b6(b3(a5(a2(x1))))))))))) (68)
a6(b7(a3(a1(a4(b6(b3(a1(a4(x1))))))))) a6(b7(a3(a1(a0(b0(b4(b6(b3(a1(a4(x1))))))))))) (69)
a6(b7(a3(a1(a4(b6(b3(a1(a0(x1))))))))) a6(b7(a3(a1(a0(b0(b4(b6(b3(a1(a0(x1))))))))))) (70)
a4(b6(b3(a1(a4(b6(b7(a7(a7(x1))))))))) a4(b6(b3(a1(a0(b0(b4(b6(b7(a7(a7(x1))))))))))) (71)
a4(b6(b3(a1(a4(b6(b7(a7(a3(x1))))))))) a4(b6(b3(a1(a0(b0(b4(b6(b7(a7(a3(x1))))))))))) (72)
a4(b6(b3(a1(a4(b6(b7(a3(a5(x1))))))))) a4(b6(b3(a1(a0(b0(b4(b6(b7(a3(a5(x1))))))))))) (73)
a4(b6(b3(a1(a4(b6(b7(a3(a1(x1))))))))) a4(b6(b3(a1(a0(b0(b4(b6(b7(a3(a1(x1))))))))))) (74)
a4(b6(b3(a1(a4(b6(b3(a5(a6(x1))))))))) a4(b6(b3(a1(a0(b0(b4(b6(b3(a5(a6(x1))))))))))) (75)
a4(b6(b3(a1(a4(b6(b3(a5(a2(x1))))))))) a4(b6(b3(a1(a0(b0(b4(b6(b3(a5(a2(x1))))))))))) (76)
a4(b6(b3(a1(a4(b6(b3(a1(a4(x1))))))))) a4(b6(b3(a1(a0(b0(b4(b6(b3(a1(a4(x1))))))))))) (77)
a4(b6(b3(a1(a4(b6(b3(a1(a0(x1))))))))) a4(b6(b3(a1(a0(b0(b4(b6(b3(a1(a0(x1))))))))))) (78)
b7(a7(a3(a1(a4(b6(b7(a7(a7(x1))))))))) b7(a7(a3(a1(a0(b0(b4(b6(b7(a7(a7(x1))))))))))) (79)
b7(a7(a3(a1(a4(b6(b7(a7(a3(x1))))))))) b7(a7(a3(a1(a0(b0(b4(b6(b7(a7(a3(x1))))))))))) (80)
b7(a7(a3(a1(a4(b6(b7(a3(a5(x1))))))))) b7(a7(a3(a1(a0(b0(b4(b6(b7(a3(a5(x1))))))))))) (81)
b7(a7(a3(a1(a4(b6(b7(a3(a1(x1))))))))) b7(a7(a3(a1(a0(b0(b4(b6(b7(a3(a1(x1))))))))))) (82)
b7(a7(a3(a1(a4(b6(b3(a5(a6(x1))))))))) b7(a7(a3(a1(a0(b0(b4(b6(b3(a5(a6(x1))))))))))) (83)
b7(a7(a3(a1(a4(b6(b3(a5(a2(x1))))))))) b7(a7(a3(a1(a0(b0(b4(b6(b3(a5(a2(x1))))))))))) (84)
b7(a7(a3(a1(a4(b6(b3(a1(a4(x1))))))))) b7(a7(a3(a1(a0(b0(b4(b6(b3(a1(a4(x1))))))))))) (85)
b7(a7(a3(a1(a4(b6(b3(a1(a0(x1))))))))) b7(a7(a3(a1(a0(b0(b4(b6(b3(a1(a0(x1))))))))))) (86)
b5(a6(b3(a1(a4(b6(b7(a7(a7(x1))))))))) b5(a6(b3(a1(a0(b0(b4(b6(b7(a7(a7(x1))))))))))) (87)
b5(a6(b3(a1(a4(b6(b7(a7(a3(x1))))))))) b5(a6(b3(a1(a0(b0(b4(b6(b7(a7(a3(x1))))))))))) (88)
b5(a6(b3(a1(a4(b6(b7(a3(a5(x1))))))))) b5(a6(b3(a1(a0(b0(b4(b6(b7(a3(a5(x1))))))))))) (89)
b5(a6(b3(a1(a4(b6(b7(a3(a1(x1))))))))) b5(a6(b3(a1(a0(b0(b4(b6(b7(a3(a1(x1))))))))))) (90)
b5(a6(b3(a1(a4(b6(b3(a5(a6(x1))))))))) b5(a6(b3(a1(a0(b0(b4(b6(b3(a5(a6(x1))))))))))) (91)
b5(a6(b3(a1(a4(b6(b3(a5(a2(x1))))))))) b5(a6(b3(a1(a0(b0(b4(b6(b3(a5(a2(x1))))))))))) (92)
b5(a6(b3(a1(a4(b6(b3(a1(a4(x1))))))))) b5(a6(b3(a1(a0(b0(b4(b6(b3(a1(a4(x1))))))))))) (93)
b5(a6(b3(a1(a4(b6(b3(a1(a0(x1))))))))) b5(a6(b3(a1(a0(b0(b4(b6(b3(a1(a0(x1))))))))))) (94)
b6(b7(a3(a1(a4(b6(b7(a7(a7(x1))))))))) b6(b7(a3(a1(a0(b0(b4(b6(b7(a7(a7(x1))))))))))) (95)
b6(b7(a3(a1(a4(b6(b7(a7(a3(x1))))))))) b6(b7(a3(a1(a0(b0(b4(b6(b7(a7(a3(x1))))))))))) (96)
b6(b7(a3(a1(a4(b6(b7(a3(a5(x1))))))))) b6(b7(a3(a1(a0(b0(b4(b6(b7(a3(a5(x1))))))))))) (97)
b6(b7(a3(a1(a4(b6(b7(a3(a1(x1))))))))) b6(b7(a3(a1(a0(b0(b4(b6(b7(a3(a1(x1))))))))))) (98)
b6(b7(a3(a1(a4(b6(b3(a5(a6(x1))))))))) b6(b7(a3(a1(a0(b0(b4(b6(b3(a5(a6(x1))))))))))) (99)
b6(b7(a3(a1(a4(b6(b3(a5(a2(x1))))))))) b6(b7(a3(a1(a0(b0(b4(b6(b3(a5(a2(x1))))))))))) (100)
b6(b7(a3(a1(a4(b6(b3(a1(a4(x1))))))))) b6(b7(a3(a1(a0(b0(b4(b6(b3(a1(a4(x1))))))))))) (101)
b6(b7(a3(a1(a4(b6(b3(a1(a0(x1))))))))) b6(b7(a3(a1(a0(b0(b4(b6(b3(a1(a0(x1))))))))))) (102)
b4(b6(b3(a1(a4(b6(b7(a7(a7(x1))))))))) b4(b6(b3(a1(a0(b0(b4(b6(b7(a7(a7(x1))))))))))) (103)
b4(b6(b3(a1(a4(b6(b7(a7(a3(x1))))))))) b4(b6(b3(a1(a0(b0(b4(b6(b7(a7(a3(x1))))))))))) (104)
b4(b6(b3(a1(a4(b6(b7(a3(a5(x1))))))))) b4(b6(b3(a1(a0(b0(b4(b6(b7(a3(a5(x1))))))))))) (105)
b4(b6(b3(a1(a4(b6(b7(a3(a1(x1))))))))) b4(b6(b3(a1(a0(b0(b4(b6(b7(a3(a1(x1))))))))))) (106)
b4(b6(b3(a1(a4(b6(b3(a5(a6(x1))))))))) b4(b6(b3(a1(a0(b0(b4(b6(b3(a5(a6(x1))))))))))) (107)
b4(b6(b3(a1(a4(b6(b3(a5(a2(x1))))))))) b4(b6(b3(a1(a0(b0(b4(b6(b3(a5(a2(x1))))))))))) (108)
b4(b6(b3(a1(a4(b6(b3(a1(a4(x1))))))))) b4(b6(b3(a1(a0(b0(b4(b6(b3(a1(a4(x1))))))))))) (109)
b4(b6(b3(a1(a4(b6(b3(a1(a0(x1))))))))) b4(b6(b3(a1(a0(b0(b4(b6(b3(a1(a0(x1))))))))))) (110)
a5(a6(b3(a5(a6(x1))))) a5(a6(b7(a7(a7(a7(a3(a5(a6(x1))))))))) (123)
a5(a6(b3(a5(a2(x1))))) a5(a6(b7(a7(a7(a7(a3(a5(a2(x1))))))))) (124)
a5(a6(b3(a1(a4(x1))))) a5(a6(b7(a7(a7(a7(a3(a1(a4(x1))))))))) (125)
a5(a6(b3(a1(a0(x1))))) a5(a6(b7(a7(a7(a7(a3(a1(a0(x1))))))))) (126)
a4(b6(b3(a5(a6(x1))))) a4(b6(b7(a7(a7(a7(a3(a5(a6(x1))))))))) (139)
a4(b6(b3(a5(a2(x1))))) a4(b6(b7(a7(a7(a7(a3(a5(a2(x1))))))))) (140)
a4(b6(b3(a1(a4(x1))))) a4(b6(b7(a7(a7(a7(a3(a1(a4(x1))))))))) (141)
a4(b6(b3(a1(a0(x1))))) a4(b6(b7(a7(a7(a7(a3(a1(a0(x1))))))))) (142)
b5(a6(b3(a5(a6(x1))))) b5(a6(b7(a7(a7(a7(a3(a5(a6(x1))))))))) (155)
b5(a6(b3(a5(a2(x1))))) b5(a6(b7(a7(a7(a7(a3(a5(a2(x1))))))))) (156)
b5(a6(b3(a1(a4(x1))))) b5(a6(b7(a7(a7(a7(a3(a1(a4(x1))))))))) (157)
b5(a6(b3(a1(a0(x1))))) b5(a6(b7(a7(a7(a7(a3(a1(a0(x1))))))))) (158)
b4(b6(b3(a5(a6(x1))))) b4(b6(b7(a7(a7(a7(a3(a5(a6(x1))))))))) (171)
b4(b6(b3(a5(a2(x1))))) b4(b6(b7(a7(a7(a7(a3(a5(a2(x1))))))))) (172)
b4(b6(b3(a1(a4(x1))))) b4(b6(b7(a7(a7(a7(a3(a1(a4(x1))))))))) (173)
b4(b6(b3(a1(a0(x1))))) b4(b6(b7(a7(a7(a7(a3(a1(a0(x1))))))))) (174)
a3(a1(a4(b6(b7(x1))))) a3(a1(a0(b0(b0(b0(b4(b6(b7(x1))))))))) (175)
a3(a1(a4(b6(b3(x1))))) a3(a1(a0(b0(b0(b0(b4(b6(b3(x1))))))))) (176)
a3(a1(a4(b2(b5(x1))))) a3(a1(a0(b0(b0(b0(b4(b2(b5(x1))))))))) (177)
a3(a1(a4(b2(b1(x1))))) a3(a1(a0(b0(b0(b0(b4(b2(b1(x1))))))))) (178)
a2(b1(a4(b6(b7(x1))))) a2(b1(a0(b0(b0(b0(b4(b6(b7(x1))))))))) (191)
a2(b1(a4(b6(b3(x1))))) a2(b1(a0(b0(b0(b0(b4(b6(b3(x1))))))))) (192)
a2(b1(a4(b2(b5(x1))))) a2(b1(a0(b0(b0(b0(b4(b2(b5(x1))))))))) (193)
a2(b1(a4(b2(b1(x1))))) a2(b1(a0(b0(b0(b0(b4(b2(b1(x1))))))))) (194)
b3(a1(a4(b6(b7(x1))))) b3(a1(a0(b0(b0(b0(b4(b6(b7(x1))))))))) (207)
b3(a1(a4(b6(b3(x1))))) b3(a1(a0(b0(b0(b0(b4(b6(b3(x1))))))))) (208)
b3(a1(a4(b2(b5(x1))))) b3(a1(a0(b0(b0(b0(b4(b2(b5(x1))))))))) (209)
b3(a1(a4(b2(b1(x1))))) b3(a1(a0(b0(b0(b0(b4(b2(b1(x1))))))))) (210)
b2(b1(a4(b6(b7(x1))))) b2(b1(a0(b0(b0(b0(b4(b6(b7(x1))))))))) (223)
b2(b1(a4(b6(b3(x1))))) b2(b1(a0(b0(b0(b0(b4(b6(b3(x1))))))))) (224)
b2(b1(a4(b2(b5(x1))))) b2(b1(a0(b0(b0(b0(b4(b2(b5(x1))))))))) (225)
b2(b1(a4(b2(b1(x1))))) b2(b1(a0(b0(b0(b0(b4(b2(b1(x1))))))))) (226)

1.1.1.1.1.1.1 R is empty

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