(0) Obligation:
Q restricted rewrite system:
The TRS R consists of the following rules:
f(f(a, x), y) → f(f(x, f(a, y)), a)
Q is empty.
(1) Overlay + Local Confluence (EQUIVALENT transformation)
The TRS is overlay and locally confluent. By [NOC] we can switch to innermost.
(2) Obligation:
Q restricted rewrite system:
The TRS R consists of the following rules:
f(f(a, x), y) → f(f(x, f(a, y)), a)
The set Q consists of the following terms:
f(f(a, x0), x1)
(3) DependencyPairsProof (EQUIVALENT transformation)
Using Dependency Pairs [AG00,LPAR04] we result in the following initial DP problem.
(4) Obligation:
Q DP problem:
The TRS P consists of the following rules:
F(f(a, x), y) → F(f(x, f(a, y)), a)
F(f(a, x), y) → F(x, f(a, y))
F(f(a, x), y) → F(a, y)
The TRS R consists of the following rules:
f(f(a, x), y) → f(f(x, f(a, y)), a)
The set Q consists of the following terms:
f(f(a, x0), x1)
We have to consider all minimal (P,Q,R)-chains.
(5) DependencyGraphProof (EQUIVALENT transformation)
The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node.
(6) Obligation:
Q DP problem:
The TRS P consists of the following rules:
F(f(a, x), y) → F(x, f(a, y))
F(f(a, x), y) → F(f(x, f(a, y)), a)
The TRS R consists of the following rules:
f(f(a, x), y) → f(f(x, f(a, y)), a)
The set Q consists of the following terms:
f(f(a, x0), x1)
We have to consider all minimal (P,Q,R)-chains.