Certification Problem

Input (COPS 178)

We consider the TRS containing the following rules:

+(+(x,y),z) +(x,+(y,z)) (1)
+(x,+(y,z)) +(+(x,y),z) (2)
+(x,y) +(y,x) (3)

The underlying signature is as follows:

{+/2}

Property / Task

Prove or disprove confluence.

Answer / Result

Yes.

Proof (by ACP @ CoCo 2020)

1 Strongly closed

Confluence is proven since the TRS is strongly closed. The joins can be performed using 12 step(s).