Certification Problem

Input (TPDB TRS_Standard/Transformed_CSR_04/PEANO_nosorts-noand_FR)

The rewrite relation of the following TRS is considered.

U11(tt,M,N) U12(tt,activate(M),activate(N)) (1)
U12(tt,M,N) s(plus(activate(N),activate(M))) (2)
plus(N,0) N (3)
plus(N,s(M)) U11(tt,M,N) (4)
activate(X) X (5)

Property / Task

Prove or disprove termination.

Answer / Result

Yes.

Proof (by AProVE @ termCOMP 2023)

1 Rule Removal

Using the linear polynomial interpretation over the naturals
[U11(x1, x2, x3)] = 1 · x1 + 1 · x2 + 2 · x3
[tt] = 0
[U12(x1, x2, x3)] = 1 · x1 + 1 · x2 + 2 · x3
[activate(x1)] = 1 · x1
[s(x1)] = 1 · x1
[plus(x1, x2)] = 2 · x1 + 1 · x2
[0] = 2
all of the following rules can be deleted.
plus(N,0) N (3)

1.1 Rule Removal

Using the Knuth Bendix order with w0 = 1 and the following precedence and weight functions
prec(tt) = 3 weight(tt) = 2
prec(activate) = 5 weight(activate) = 0
prec(s) = 0 weight(s) = 1
prec(U11) = 2 weight(U11) = 0
prec(U12) = 1 weight(U12) = 0
prec(plus) = 4 weight(plus) = 1
all of the following rules can be deleted.
U11(tt,M,N) U12(tt,activate(M),activate(N)) (1)
U12(tt,M,N) s(plus(activate(N),activate(M))) (2)
plus(N,s(M)) U11(tt,M,N) (4)
activate(X) X (5)

1.1.1 R is empty

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