Certification Problem

Input (TPDB TRS_Standard/AG01/#3.53a)

The rewrite relation of the following TRS is considered.

g(x,y) x (1)
g(x,y) y (2)
f(s(x),y,y) f(y,x,s(x)) (3)

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
[g(x1, x2)] = 1 · x1 + 1 · x2
[f(x1, x2, x3)] = 2 · x1 + 1 · x2 + 1 · x3
[s(x1)] = 2 + 2 · x1
all of the following rules can be deleted.
f(s(x),y,y) f(y,x,s(x)) (3)

1.1 Rule Removal

Using the linear polynomial interpretation over the naturals
[g(x1, x2)] = 1 + 1 · x1 + 1 · x2
all of the following rules can be deleted.
g(x,y) x (1)
g(x,y) y (2)

1.1.1 R is empty

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