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, r2 Take the reduction pair: generalized weighted path order (>=MG, >MG) base order 1: max/plus interpretation on natural numbers: fac#_A(x1) = max{3, x1 - 5} s_A(x1) = x1 + 9 p_A(x1) = max{4, x1 - 7} fac_A(x1) = 11 |0|_A = 1 base order 2: precedence: fac > |0| > fac# = s > p partial status: pi(fac#) = [] pi(s) = [] pi(p) = [] pi(fac) = [] pi(|0|) = [] The following rules are removed: p1 Then no dependency pair remains.