Problem: a(x1) -> x1 a(b(x1)) -> b(a(a(c(b(x1))))) b(x1) -> a(x1) c(c(x1)) -> x1 Proof: Unfolding Processor: loop length: 7 terms: a(b(c(b(x3778)))) b(a(a(c(b(c(b(x3778))))))) b(a(a(c(a(c(b(x3778))))))) b(a(a(c(c(b(x3778)))))) b(a(a(b(x3778)))) b(a(b(a(a(c(b(x3778))))))) b(a(b(a(c(b(x3778)))))) context: b([]) substitution: x3778 -> x3778 Qed