let R be the TRS under consideration

f(g(_1),_1,_2) -> f(_2,_2,g(_2)) is in elim_R(R)
let r0 be the right-hand side of this rule
p0 = 1 is a position in r0
we have r0|p0 = _2
g(g(_3)) -> g(_3) is in R
let l'0 be the left-hand side of this rule
theta0 = {_2/g(g(_3))} is a mgu of r0|p0 and l'0

==> f(g(_1),_1,g(g(_2))) -> f(g(g(_2)),g(_2),g(g(g(_2)))) is in EU_R^1
let l be the left-hand side and r be the right-hand side of this rule
let p = epsilon
let theta = {}
let theta' = {_1/g(_2), _2/g(_2)}
we have r|p = f(g(g(_2)),g(_2),g(g(g(_2)))) and
theta'(theta(l)) = theta(r|p)
so, theta(l) = f(g(_1),_1,g(g(_2))) is non-terminating w.r.t. R

Termination disproved by the forward process
proof stopped at iteration i=1, depth k=2
2 rule(s) generated