Certification Problem

Input (TPDB SRS_Relative/Waldmann_06_relative/r9)

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

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

and S is the following TRS.

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

Property / Task

Prove or disprove termination.

Answer / Result

Yes.

Proof (by ttt2 @ termCOMP 2023)

1 Rule Removal

Using the linear polynomial interpretation over (4 x 4)-matrices with strict dimension 1 over the naturals
[a(x1)] =
1 0 0 1
0 0 0 1
0 1 0 0
0 0 1 0
· x1 +
0 0 0 0
1 0 0 0
0 0 0 0
0 0 0 0
[b(x1)] =
1 1 0 0
0 0 0 0
0 0 0 0
0 0 0 0
· x1 +
0 0 0 0
0 0 0 0
0 0 0 0
1 0 0 0
all of the following rules can be deleted.
b(a(b(x1))) b(a(a(a(b(x1))))) (1)

1.1 R is empty

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