YES We show the termination of the TRS R: g(|0|()) -> |0|() g(s(x)) -> f(g(x)) f(|0|()) -> |0|() -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: g#(s(x)) -> f#(g(x)) p2: g#(s(x)) -> g#(x) and R consists of: r1: g(|0|()) -> |0|() r2: g(s(x)) -> f(g(x)) r3: f(|0|()) -> |0|() The estimated dependency graph contains the following SCCs: {p2} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: g#(s(x)) -> g#(x) and R consists of: r1: g(|0|()) -> |0|() r2: g(s(x)) -> f(g(x)) r3: f(|0|()) -> |0|() The set of usable rules consists of (no rules) Take the monotone reduction pair: lexicographic combination of reduction pairs: 1. lexicographic path order with precedence: precedence: s > g# argument filter: pi(g#) = [1] pi(s) = [1] 2. lexicographic path order with precedence: precedence: s > g# argument filter: pi(g#) = [1] pi(s) = [1] 3. lexicographic path order with precedence: precedence: s > g# argument filter: pi(g#) = [1] pi(s) = [1] The next rules are strictly ordered: p1 r1, r2, r3 We remove them from the problem. Then no dependency pair remains.