NO Problem: a(x1) -> x1 a(b(x1)) -> b(a(a(c(b(a(x1)))))) b(x1) -> x1 c(c(x1)) -> x1 Proof: Unfolding Processor: loop length: 7 terms: a(b(c(b(x16562)))) b(a(a(c(b(a(c(b(x16562)))))))) b(a(a(c(a(c(b(x16562))))))) b(a(a(c(c(b(x16562)))))) b(a(a(b(x16562)))) b(a(b(a(a(c(b(a(x16562)))))))) b(a(b(a(c(b(a(x16562))))))) context: b([]) substitution: x16562 -> a(x16562) Qed