NO
Non-Confluence Proof
Non-Confluence Proof
by Hakusan
Input
The rewrite relation of the following TRS is considered.
a(x) |
→ |
g(h(b(x))) |
a(x) |
→ |
g(c(x)) |
b(x) |
→ |
g(b(x)) |
g(a(x)) |
→ |
g(h(a(x))) |
Proof
1 Non-Joinable Fork
The system is not confluent due to the following forking derivations.
t0
|
= |
a(y1) |
|
→ε
|
g(c(y1)) |
|
= |
t1
|
t0
|
= |
a(y1) |
|
→ε
|
g(h(b(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