YES We show the termination of the TRS R: p(s(x)) -> x fac(|0|()) -> s(|0|()) fac(s(x)) -> times(s(x),fac(p(s(x)))) -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: fac#(s(x)) -> fac#(p(s(x))) p2: fac#(s(x)) -> p#(s(x)) and R consists of: r1: p(s(x)) -> x r2: fac(|0|()) -> s(|0|()) r3: fac(s(x)) -> times(s(x),fac(p(s(x)))) The estimated dependency graph contains the following SCCs: {p1} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: fac#(s(x)) -> fac#(p(s(x))) and R consists of: r1: p(s(x)) -> x r2: fac(|0|()) -> s(|0|()) r3: fac(s(x)) -> times(s(x),fac(p(s(x)))) The set of usable rules consists of r1 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: trivial reduction triple (T x T, T x T, Φ) base order 2: lexicographic combination of reduction triples: 1. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: fac#_A(x1) = max{0, x1 - 19} s_A(x1) = max{18, x1 + 3} p_A(x1) = max{7, x1 - 3} fac#!_A(x1) = max{1, x1 - 16} s!_A(x1) = 3 p!_A(x1) = 4 2. marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: fac#_A(x1) = x1 s_A(x1) = x1 + 1 p_A(x1) = x1 fac#!_A(x1) = 0 s!_A(x1) = 1 p!_A(x1) = x1 + 3 partial status: pi(fac#) = [] pi(s) = [1] pi(p) = [1] The following rules are removed: p1 Then no dependency pair remains.