YES Termination Proof

Termination Proof

by ttt2 (version ttt2 1.15)

Input

The rewrite relation of the following TRS is considered.

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

Proof

1 Rule Removal

Using the linear polynomial interpretation over (3 x 3)-matrices with strict dimension 1 over the arctic semiring over the integers
[b(x1)] =
0 0 -∞
0 1 1
-∞ 0 0
· x1 +
-∞ -∞ -∞
-∞ -∞ -∞
-∞ -∞ -∞
[a(x1)] =
0 1 0
-∞ 0 -∞
0 1 0
· x1 +
-∞ -∞ -∞
-∞ -∞ -∞
-∞ -∞ -∞
[c(x1)] =
0 0 0
-∞ -∞ 0
-∞ 0 -∞
· x1 +
-∞ -∞ -∞
-∞ -∞ -∞
-∞ -∞ -∞
the rules
a(x0) x0
a(c(c(x0))) c(c(a(a(x0))))
remain.

1.1 Rule Removal

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

1.1.1 R is empty

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