Certification Problem

Input (TPDB SRS_Standard/ICFP_2010/68535)

The rewrite relation of the following TRS is considered.

0(0(1(1(x1)))) → 2(2(1(3(x1)))) (1)
1(4(0(4(x1)))) → 1(2(3(1(x1)))) (2)
3(4(3(1(1(x1))))) → 3(4(0(3(1(x1))))) (3)
1(3(1(1(0(4(x1)))))) → 1(3(0(2(0(4(x1)))))) (4)
2(4(4(5(4(4(3(x1))))))) → 2(4(2(3(4(2(2(x1))))))) (5)
5(5(4(2(0(2(3(x1))))))) → 5(2(4(1(2(3(3(x1))))))) (6)
0(4(5(2(1(2(0(1(x1)))))))) → 0(1(5(4(2(5(0(0(x1)))))))) (7)
4(4(1(4(0(0(1(3(x1)))))))) → 4(1(2(3(4(2(5(3(x1)))))))) (8)
4(3(0(2(5(3(1(2(3(x1))))))))) → 4(1(1(0(0(0(5(3(x1)))))))) (9)
4(0(5(5(3(2(1(0(0(0(x1)))))))))) → 1(4(3(3(4(3(3(1(0(0(x1)))))))))) (10)
4(1(5(2(4(0(1(1(0(1(x1)))))))))) → 0(1(0(2(5(0(5(3(5(4(x1)))))))))) (11)
3(0(4(4(4(5(3(1(2(5(0(4(x1)))))))))))) → 5(3(3(0(3(5(1(0(0(1(0(x1))))))))))) (12)
4(5(2(2(5(1(5(0(4(0(1(1(x1)))))))))))) → 4(1(1(4(3(2(2(3(5(2(1(3(x1)))))))))))) (13)
5(4(2(3(0(4(3(2(2(2(4(1(x1)))))))))))) → 5(1(0(2(4(4(4(5(1(4(1(x1))))))))))) (14)
3(0(0(2(1(1(3(1(5(0(5(1(0(5(x1)))))))))))))) → 5(1(0(1(2(2(1(3(3(1(0(2(5(x1))))))))))))) (15)
0(4(2(4(1(1(5(3(0(2(2(0(5(1(5(x1))))))))))))))) → 1(1(0(0(3(5(5(1(1(2(5(3(5(5(x1)))))))))))))) (16)
0(5(1(3(5(4(4(0(5(1(2(0(0(5(3(x1))))))))))))))) → 0(4(0(0(3(4(3(3(5(0(4(3(3(1(3(x1))))))))))))))) (17)
2(4(2(0(0(1(3(4(2(1(5(2(2(0(4(1(x1)))))))))))))))) → 3(2(2(3(4(1(2(1(0(3(1(2(3(2(1(1(x1)))))))))))))))) (18)
0(0(0(2(0(3(0(5(1(0(5(0(5(1(0(4(3(x1))))))))))))))))) → 0(0(1(4(5(0(0(2(0(0(1(1(3(2(5(3(x1)))))))))))))))) (19)
1(4(0(4(0(4(0(2(2(5(5(3(1(1(0(0(3(x1))))))))))))))))) → 1(1(0(0(3(4(4(4(4(4(2(3(3(1(0(4(3(x1))))))))))))))))) (20)
2(2(5(1(1(3(5(4(0(5(5(2(4(1(4(4(1(x1))))))))))))))))) → 4(1(1(2(3(3(1(1(4(5(3(1(3(2(4(0(2(x1))))))))))))))))) (21)
1(0(3(3(1(4(3(3(5(0(4(2(4(3(4(2(0(2(x1)))))))))))))))))) → 1(0(5(1(0(2(0(0(4(0(2(5(0(2(5(2(2(2(x1)))))))))))))))))) (22)
2(4(2(1(5(5(0(1(0(4(2(2(2(3(4(1(0(4(x1)))))))))))))))))) → 2(1(3(2(1(2(2(5(1(1(3(5(4(4(5(5(5(x1))))))))))))))))) (23)
5(4(2(2(4(2(1(1(0(5(1(5(2(4(0(1(3(5(x1)))))))))))))))))) → 5(1(2(2(3(1(5(2(5(1(1(3(4(2(4(0(5(5(x1)))))))))))))))))) (24)
0(1(2(4(3(4(2(1(1(0(4(5(4(0(4(5(4(5(3(4(1(x1))))))))))))))))))))) → 2(4(0(1(5(0(1(2(3(0(4(1(4(1(5(3(4(1(5(0(2(x1))))))))))))))))))))) (25)

Property / Task

Prove or disprove termination.

Answer / Result

Yes.

Proof (by matchbox @ termCOMP 2023)

1 Rule Removal

Using the matrix interpretations of dimension 1 with strict dimension 1 over the rationals with delta = 1
[5(x1)] = x1 +
1
[4(x1)] = x1 +
1
[3(x1)] = x1 +
1
[2(x1)] = x1 +
1
[1(x1)] = x1 +
1
[0(x1)] = x1 +
1
all of the following rules can be deleted.
4(3(0(2(5(3(1(2(3(x1))))))))) → 4(1(1(0(0(0(5(3(x1)))))))) (9)
3(0(4(4(4(5(3(1(2(5(0(4(x1)))))))))))) → 5(3(3(0(3(5(1(0(0(1(0(x1))))))))))) (12)
5(4(2(3(0(4(3(2(2(2(4(1(x1)))))))))))) → 5(1(0(2(4(4(4(5(1(4(1(x1))))))))))) (14)
3(0(0(2(1(1(3(1(5(0(5(1(0(5(x1)))))))))))))) → 5(1(0(1(2(2(1(3(3(1(0(2(5(x1))))))))))))) (15)
0(4(2(4(1(1(5(3(0(2(2(0(5(1(5(x1))))))))))))))) → 1(1(0(0(3(5(5(1(1(2(5(3(5(5(x1)))))))))))))) (16)
0(0(0(2(0(3(0(5(1(0(5(0(5(1(0(4(3(x1))))))))))))))))) → 0(0(1(4(5(0(0(2(0(0(1(1(3(2(5(3(x1)))))))))))))))) (19)
2(4(2(1(5(5(0(1(0(4(2(2(2(3(4(1(0(4(x1)))))))))))))))))) → 2(1(3(2(1(2(2(5(1(1(3(5(4(4(5(5(5(x1))))))))))))))))) (23)

1.1 Closure Under Flat Contexts

Using the flat contexts

{5(☐), 4(☐), 3(☐), 2(☐), 1(☐), 0(☐)}

We obtain the transformed TRS

There are 108 ruless (increase limit for explicit display).

1.1.1 Semantic Labeling

The following interpretations form a model of the rules.

As carrier we take the set {0,...,5}. Symbols are labeled by the interpretation of their arguments using the interpretations (modulo 6):

[5(x1)] = 6x1 + 0
[4(x1)] = 6x1 + 1
[3(x1)] = 6x1 + 2
[2(x1)] = 6x1 + 3
[1(x1)] = 6x1 + 4
[0(x1)] = 6x1 + 5

We obtain the labeled TRS

There are 648 ruless (increase limit for explicit display).

1.1.1.1 Rule Removal

Using the matrix interpretations of dimension 1 with strict dimension 1 over the rationals with delta = 1
[50(x1)] = x1 +
25
[51(x1)] = x1 +
24
[52(x1)] = x1 +
1
[53(x1)] = x1 +
24
[54(x1)] = x1 +
24
[55(x1)] = x1 +
0
[40(x1)] = x1 +
25
[41(x1)] = x1 +
9
[42(x1)] = x1 +
24
[43(x1)] = x1 +
24
[44(x1)] = x1 +
0
[45(x1)] = x1 +
24
[30(x1)] = x1 +
1
[31(x1)] = x1 +
18
[32(x1)] = x1 +
0
[33(x1)] = x1 +
0
[34(x1)] = x1 +
1
[35(x1)] = x1 +
1
[20(x1)] = x1 +
0
[21(x1)] = x1 +
25
[22(x1)] = x1 +
0
[23(x1)] = x1 +
0
[24(x1)] = x1 +
1
[25(x1)] = x1 +
24
[10(x1)] = x1 +
0
[11(x1)] = x1 +
7
[12(x1)] = x1 +
0
[13(x1)] = x1 +
1
[14(x1)] = x1 +
24
[15(x1)] = x1 +
24
[00(x1)] = x1 +
24
[01(x1)] = x1 +
25
[02(x1)] = x1 +
1
[03(x1)] = x1 +
0
[04(x1)] = x1 +
24
[05(x1)] = x1 +
24
all of the following rules can be deleted.

There are 648 ruless (increase limit for explicit display).

1.1.1.1.1 R is empty

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