Problem: f(0(),1(),X) -> f(g(X,X),X,X) g(X,Y) -> X g(X,Y) -> Y Proof: Unfolding Processor: loop length: 4 terms: f(g(0(),1()),g(0(),1()),g(0(),1())) f(g(0(),1()),1(),g(0(),1())) f(0(),1(),g(0(),1())) f(g(g(0(),1()),g(0(),1())),g(0(),1()),g(0(),1())) context: [] substitution: Qed