NO
Non-Confluence Proof
Non-Confluence Proof
by Hakusan
Input
The rewrite relation of the following TRS is considered.
| 
W(B(x)) | 
→ | 
I(x) | 
| 
B(S(x)) | 
→ | 
S(x) | 
| 
W(x) | 
→ | 
I(x) | 
Proof
1 Non-Joinable Fork
        The system is not confluent due to the following forking derivations.  
        
| t0
 | 
= | 
W(B(y1)) | 
 | 
→ε
 | 
I(B(y1)) | 
 | 
= | 
t1
 | 
| t0
 | 
= | 
W(B(y1)) | 
 | 
→ε
 | 
I(y1) | 
 | 
= | 
t1
 | 
            
        The two resulting terms cannot be joined for the following reason:
        - When applying the cap-function on both terms (where variables may be treated like constants)
            then the resulting terms do not unify.
 
Tool configuration
Hakusan