ceta_eq: termination proof not accepted 1: error below switch to dependency pairs 1.1: error below the dependency graph processor 1.1.1: error when applying the reduction pair processor to remove from the DP problem pairs: f#(a, f(f(a, x), a)) -> f#(a, f(a, x)) rules: f(a, f(f(a, x), a)) -> f(f(a, f(a, x)), a) the pairs f#(a, f(f(a, x), a)) -> f#(a, f(a, x)) could not apply the generic reduction pair processor with the following Argument Filter: pi(f#/2) = [2] pi(a/0) = [] pi(f/2) = [1,2] RPO with the following precedence precedence(f#[2]) = 0 precedence(a[0]) = 0 precedence(f[2]) = 1 precedence(_) = 0 and the following status status(f#[2]) = mul status(a[0]) = mul status(f[2]) = mul status(_) = lex problem when orienting (usable) rules could not orient f(a, f(f(a, x), a)) >= f(f(a, f(a, x)), a) pi( f(a, f(f(a, x), a)) ) = f(a, f(f(a, x), a)) pi( f(f(a, f(a, x)), a) ) = f(f(a, f(a, x)), a) could not orient f(a, f(f(a, x), a)) >=RPO f(f(a, f(a, x)), a)