Certification Problem

Input (COPS 1060)

We consider two TRSs R and S where R contains the rules

a b (1)
a d (2)
b a (3)
c a (4)
c b (5)

and S contains the following rules:

a b (1)
a c (6)
a e (7)
b d (8)
c a (4)
d a (9)
d e (10)
g(x) h(a) (11)
h(x) e (12)

The underlying signature is as follows:

{a/0, b/0, c/0, d/0, e/0, g/1, h/1}

Property / Task

Prove or disprove commutation.

Answer / Result

Yes.

Proof (by ACP @ CoCo 2023)

1 Swap TRSs

The role of TRSs R and S are changed.

1.1 Development Closed

Commutation is proven since the TRSs are development closed. The joins can be performed using 5 step(s).