Certification Problem

Input (TPDB TRS_Standard/Strategy_removed_mixed_05/bn111)

The rewrite relation of the following TRS is considered.

f(f(X,Y),Z) f(X,f(Y,Z)) (1)
f(X,f(Y,Z)) f(Y,Y) (2)

Property / Task

Prove or disprove termination.

Answer / Result

Yes.

Proof (by AProVE @ termCOMP 2023)

1 Dependency Pair Transformation

The following set of initial dependency pairs has been identified.
f#(f(X,Y),Z) f#(X,f(Y,Z)) (3)
f#(f(X,Y),Z) f#(Y,Z) (4)
f#(X,f(Y,Z)) f#(Y,Y) (5)

1.1 Reduction Pair Processor

Using the non-linear polynomial interpretation over the naturals
[f#(x1, x2)] = 2 · x2 + 1 · x1 · x2 + 2 · x1 · x1
[f(x1, x2)] = 2 + 2 · x1 + 2 · x2 + 1 · x1 · x2 + 2 · x1 · x1
the pairs
f#(f(X,Y),Z) f#(X,f(Y,Z)) (3)
f#(f(X,Y),Z) f#(Y,Z) (4)
f#(X,f(Y,Z)) f#(Y,Y) (5)
could be deleted.

1.1.1 P is empty

There are no pairs anymore.