Certification Problem

Input (TPDB SRS_Standard/ICFP_2010/4074)

The rewrite relation of the following TRS is considered.

1(5(4(0(x1)))) → 3(3(2(3(1(4(4(4(3(4(x1)))))))))) (1)
0(5(1(5(1(x1))))) → 0(1(4(4(3(4(4(3(2(1(x1)))))))))) (2)
1(0(2(5(3(x1))))) → 4(3(4(0(5(4(4(4(4(3(x1)))))))))) (3)
1(5(2(1(5(x1))))) → 3(4(3(2(2(2(2(4(4(5(x1)))))))))) (4)
0(5(1(0(5(2(x1)))))) → 2(4(3(2(1(3(4(1(4(4(x1)))))))))) (5)
0(5(3(0(4(0(x1)))))) → 0(5(3(2(4(3(3(3(4(1(x1)))))))))) (6)
0(5(4(0(2(0(x1)))))) → 0(3(4(3(3(3(0(3(1(1(x1)))))))))) (7)
1(0(3(0(5(2(x1)))))) → 3(3(4(2(4(1(2(1(4(4(x1)))))))))) (8)
1(1(2(3(1(0(x1)))))) → 1(3(3(3(2(5(0(2(2(0(x1)))))))))) (9)
1(1(3(4(5(3(x1)))))) → 3(1(4(5(5(0(0(3(3(2(x1)))))))))) (10)
1(1(5(4(0(1(x1)))))) → 1(3(2(3(5(4(4(4(5(1(x1)))))))))) (11)
1(5(0(0(1(0(x1)))))) → 3(3(3(3(2(3(0(1(1(5(x1)))))))))) (12)
1(5(0(1(3(0(x1)))))) → 4(4(2(0(3(3(4(2(0(5(x1)))))))))) (13)
1(5(1(1(3(0(x1)))))) → 1(3(2(1(4(2(0(2(2(0(x1)))))))))) (14)
2(0(3(3(5(3(x1)))))) → 4(2(0(1(1(4(3(2(3(2(x1)))))))))) (15)
3(1(0(0(4(2(x1)))))) → 3(4(2(0(1(2(4(3(2(2(x1)))))))))) (16)
3(1(0(3(0(5(x1)))))) → 2(0(3(2(3(2(2(0(4(5(x1)))))))))) (17)
4(0(5(2(0(0(x1)))))) → 3(2(2(0(2(3(3(0(5(0(x1)))))))))) (18)
4(5(2(5(1(4(x1)))))) → 4(1(1(5(5(1(2(4(1(4(x1)))))))))) (19)
5(1(0(1(0(3(x1)))))) → 5(0(2(3(2(1(4(3(0(1(x1)))))))))) (20)
5(1(0(5(4(1(x1)))))) → 5(3(3(3(3(4(3(2(3(1(x1)))))))))) (21)
5(3(0(0(2(0(x1)))))) → 4(1(4(2(4(4(3(2(4(0(x1)))))))))) (22)
0(1(3(5(3(1(1(x1))))))) → 0(0(3(3(2(2(2(5(1(1(x1)))))))))) (23)
0(5(1(5(3(0(0(x1))))))) → 0(5(3(4(3(3(3(0(0(3(x1)))))))))) (24)
0(5(3(5(1(0(3(x1))))))) → 2(3(3(3(0(0(1(1(1(3(x1)))))))))) (25)
1(0(0(4(1(1(0(x1))))))) → 4(1(2(4(3(2(3(1(1(0(x1)))))))))) (26)
1(0(0(5(3(5(3(x1))))))) → 4(4(5(5(0(0(0(0(1(1(x1)))))))))) (27)
1(0(1(3(0(4(3(x1))))))) → 4(4(5(4(4(3(3(2(4(3(x1)))))))))) (28)
1(0(5(3(0(0(4(x1))))))) → 2(3(3(4(0(4(0(5(4(3(x1)))))))))) (29)
1(3(5(1(1(4(0(x1))))))) → 4(1(3(4(4(4(3(3(5(5(x1)))))))))) (30)
1(5(1(0(1(5(1(x1))))))) → 3(4(3(1(2(2(5(1(3(3(x1)))))))))) (31)
1(5(1(5(5(3(0(x1))))))) → 3(2(4(0(5(1(2(3(2(4(x1)))))))))) (32)
1(5(3(5(5(4(0(x1))))))) → 4(4(3(5(4(2(2(2(2(1(x1)))))))))) (33)
2(0(1(5(3(1(3(x1))))))) → 2(4(0(5(0(2(2(1(1(3(x1)))))))))) (34)
2(0(3(1(5(3(0(x1))))))) → 2(0(0(3(4(2(4(1(2(4(x1)))))))))) (35)
2(3(5(1(1(0(4(x1))))))) → 3(2(3(5(0(0(2(1(2(1(x1)))))))))) (36)
2(3(5(3(5(0(1(x1))))))) → 3(2(3(2(1(5(2(4(1(1(x1)))))))))) (37)
2(5(5(3(5(1(1(x1))))))) → 2(1(2(5(0(0(0(3(4(1(x1)))))))))) (38)
3(0(4(0(0(1(0(x1))))))) → 2(2(0(4(1(3(5(1(4(1(x1)))))))))) (39)
3(1(0(5(5(0(1(x1))))))) → 4(1(0(2(3(4(0(5(0(2(x1)))))))))) (40)
3(5(3(0(0(5(2(x1))))))) → 2(2(2(4(1(2(0(4(1(1(x1)))))))))) (41)
4(0(2(5(4(0(0(x1))))))) → 3(5(2(3(2(3(2(2(4(0(x1)))))))))) (42)
4(5(1(5(2(1(0(x1))))))) → 3(5(1(4(3(3(2(5(3(4(x1)))))))))) (43)
5(1(5(4(2(2(5(x1))))))) → 5(5(1(2(3(0(3(2(1(5(x1)))))))))) (44)
5(1(5(5(2(1(3(x1))))))) → 0(1(0(3(3(2(3(2(1(3(x1)))))))))) (45)
5(2(3(0(5(2(0(x1))))))) → 5(5(3(3(3(2(4(3(5(5(x1)))))))))) (46)
5(2(3(5(1(0(5(x1))))))) → 1(1(2(1(1(2(4(3(3(5(x1)))))))))) (47)
5(3(0(3(5(2(0(x1))))))) → 4(3(1(2(4(1(1(2(2(4(x1)))))))))) (48)
5(3(1(4(0(4(0(x1))))))) → 0(5(5(5(4(4(3(4(0(0(x1)))))))))) (49)
5(3(5(2(1(1(0(x1))))))) → 5(0(3(4(5(0(2(2(5(0(x1)))))))))) (50)
5(3(5(4(2(5(3(x1))))))) → 5(5(2(3(3(0(5(5(5(1(x1)))))))))) (51)
5(5(0(1(5(3(5(x1))))))) → 1(4(1(2(4(4(0(3(2(5(x1)))))))))) (52)

Property / Task

Prove or disprove termination.

Answer / Result

Yes.

Proof (by matchbox @ termCOMP 2023)

1 Closure Under Flat Contexts

Using the flat contexts

{5(☐), 4(☐), 3(☐), 2(☐), 1(☐), 0(☐)}

We obtain the transformed TRS

There are 312 ruless (increase limit for explicit display).

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 1872 ruless (increase limit for explicit display).

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 +
1
[51(x1)] = x1 +
1034
[52(x1)] = x1 +
2261
[53(x1)] = x1 +
1974
[54(x1)] = x1 +
2269
[55(x1)] = x1 +
0
[40(x1)] = x1 +
718
[41(x1)] = x1 +
0
[42(x1)] = x1 +
0
[43(x1)] = x1 +
0
[44(x1)] = x1 +
0
[45(x1)] = x1 +
705
[30(x1)] = x1 +
2261
[31(x1)] = x1 +
0
[32(x1)] = x1 +
0
[33(x1)] = x1 +
0
[34(x1)] = x1 +
377
[35(x1)] = x1 +
2209
[20(x1)] = x1 +
1470
[21(x1)] = x1 +
0
[22(x1)] = x1 +
0
[23(x1)] = x1 +
0
[24(x1)] = x1 +
5
[25(x1)] = x1 +
0
[10(x1)] = x1 +
2292
[11(x1)] = x1 +
1
[12(x1)] = x1 +
334
[13(x1)] = x1 +
5
[14(x1)] = x1 +
329
[15(x1)] = x1 +
2269
[00(x1)] = x1 +
2256
[01(x1)] = x1 +
2209
[02(x1)] = x1 +
283
[03(x1)] = x1 +
0
[04(x1)] = x1 +
2257
[05(x1)] = x1 +
2256
all of the following rules can be deleted.

There are 1872 ruless (increase limit for explicit display).

1.1.1.1 R is empty

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