Term Rewriting System R:
[x]
f(a, f(x, a)) -> f(a, f(a, f(f(a, a), x)))

Termination of R to be shown. 



   R
     ↳Dependency Pair Analysis



R contains the following Dependency Pairs:

F(a, f(x, a)) -> F(a, f(a, f(f(a, a), x)))
F(a, f(x, a)) -> F(a, f(f(a, a), x))
F(a, f(x, a)) -> F(f(a, a), x)
F(a, f(x, a)) -> F(a, a)

Furthermore, R contains one SCC. 


   R
     ↳DPs
       →DP Problem 1
         ↳Narrowing Transformation


Dependency Pairs:

F(a, f(x, a)) -> F(f(a, a), x)
F(a, f(x, a)) -> F(a, f(f(a, a), x))
F(a, f(x, a)) -> F(a, f(a, f(f(a, a), x)))


Rule:


f(a, f(x, a)) -> f(a, f(a, f(f(a, a), x)))





On this DP problem, a Narrowing SCC transformation can be performed.
As a result of transforming the rule

F(a, f(x, a)) -> F(a, f(a, f(f(a, a), x)))
one new Dependency Pair is created:

F(a, f(a, a)) -> F(a, f(a, f(a, f(f(a, a), f(a, a)))))

The transformation is resulting in one new DP problem: 



   R
     ↳DPs
       →DP Problem 1
         ↳Nar
           →DP Problem 2
             ↳Narrowing Transformation


Dependency Pairs:

F(a, f(a, a)) -> F(a, f(a, f(a, f(f(a, a), f(a, a)))))
F(a, f(x, a)) -> F(a, f(f(a, a), x))
F(a, f(x, a)) -> F(f(a, a), x)


Rule:


f(a, f(x, a)) -> f(a, f(a, f(f(a, a), x)))





On this DP problem, a Narrowing SCC transformation can be performed.
As a result of transforming the rule

F(a, f(x, a)) -> F(f(a, a), x)
no new Dependency Pairs are created.
The transformation is resulting in one new DP problem: 



   R
     ↳DPs
       →DP Problem 1
         ↳Nar
           →DP Problem 2
             ↳Nar
             ...
               →DP Problem 3
                 ↳Narrowing Transformation


Dependency Pairs:

F(a, f(x, a)) -> F(a, f(f(a, a), x))
F(a, f(a, a)) -> F(a, f(a, f(a, f(f(a, a), f(a, a)))))


Rule:


f(a, f(x, a)) -> f(a, f(a, f(f(a, a), x)))





On this DP problem, a Narrowing SCC transformation can be performed.
As a result of transforming the rule

F(a, f(a, a)) -> F(a, f(a, f(a, f(f(a, a), f(a, a)))))
no new Dependency Pairs are created.
The transformation is resulting in one new DP problem: 



   R
     ↳DPs
       →DP Problem 1
         ↳Nar
           →DP Problem 2
             ↳Nar
             ...
               →DP Problem 4
                 ↳Remaining Obligation(s)




The following remains to be proven:
Dependency Pair:

F(a, f(x, a)) -> F(a, f(f(a, a), x))


Rule:


f(a, f(x, a)) -> f(a, f(a, f(f(a, a), x)))




Termination of R could not be shown.
Duration:
0:00 minutes