NO Problem: b() -> f(a()) a() -> c() a() -> a() h(c(),f(f(f(a())))) -> h(f(f(c())),h(b(),a())) f(f(f(f(h(h(c(),h(f(c()),f(f(h(h(h(h(f(a()),a()),c()),a()),h(h(h(b(),a()), f(h(f(h(f(b()),f(f(b())))),a()))), h(c(),f ( h ( b(),f(f(h(h(c(),f(a())),a())))))))))))), f(f(b()))))))) -> c() Proof: Nonconfluence Processor: terms: h(c(),f(f(f(c())))) *<- h(c(),f(f(f(a())))) ->* h(f(f(c())),h(b(),a())) Qed