NO Problem: b(a(a(x))) -> a(x) a(a(a(x))) -> b(b(b(x))) b(b(x)) -> a(b(a(x))) Proof: Nonconfluence Processor: terms: b(a(b(a(b(x10))))) *<- b(a(a(b(a(a(x10)))))) ->* a(a(x10)) Qed