YES Termination Proof

Termination Proof

by ttt2 (version ttt2 1.15)

Input

The rewrite relation of the following TRS is considered.

b(a(x0)) a(b(x0))
a(a(a(x0))) b(a(a(b(x0))))
b(b(b(b(x0)))) a(x0)

Proof

1 Rule Removal

Using the linear polynomial interpretation over the arctic semiring over the integers
[b(x1)] = 4 · x1 + -∞
[a(x1)] = 8 · x1 + -∞
the rules
b(a(x0)) a(b(x0))
a(a(a(x0))) b(a(a(b(x0))))
remain.

1.1 Rule Removal

Using the linear polynomial interpretation over the arctic semiring over the integers
[b(x1)] = 0 · x1 + -∞
[a(x1)] = 1 · x1 + -∞
the rule
b(a(x0)) a(b(x0))
remains.

1.1.1 Rule Removal

Using the Knuth Bendix order with w0 = 1 and the following precedence and weight function
prec(b) = 1 weight(b) = 1
prec(a) = 0 weight(a) = 1
all rules could be removed.

1.1.1.1 R is empty

There are no rules in the TRS. Hence, it is terminating.