Term Rewriting System R: [x] f(x) -> s(x) f(s(s(x))) -> s(f(f(x))) Termination of R to be shown. R contains the following Dependency Pairs: F(s(s(x))) -> F(f(x)) F(s(s(x))) -> F(x) Furthermore, R contains one SCC. SCC1: F(s(s(x))) -> F(x) F(s(s(x))) -> F(f(x)) Removing rules from R by ordering and analyzing Dependency Pairs, Usable Rules, and Usable Equations. This is possible by using the following (C_E-compatible) Polynomial ordering. Polynomial interpretation: POL(s(x_1)) = 1 + x_1 POL(F(x_1)) = 1 + x_1 POL(f(x_1)) = 1 + x_1 The following Dependency Pairs can be deleted: F(s(s(x))) -> F(x) F(s(s(x))) -> F(f(x)) This transformation is resulting in no new subcycles. Termination of R successfully shown. Duration: 2.129 seconds.