YES We show the termination of the TRS R: a(b(x)) -> b(a(x)) a(c(x)) -> x -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: a#(b(x)) -> a#(x) and R consists of: r1: a(b(x)) -> b(a(x)) r2: a(c(x)) -> x The estimated dependency graph contains the following SCCs: {p1} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: a#(b(x)) -> a#(x) and R consists of: r1: a(b(x)) -> b(a(x)) r2: a(c(x)) -> x The set of usable rules consists of (no rules) Take the reduction pair: lexicographic combination of reduction pairs: 1. weighted path order base order: max/plus interpretations on natural numbers: a#_A(x1) = max{4, x1 + 3} b_A(x1) = max{3, x1 + 2} precedence: a# = b partial status: pi(a#) = [1] pi(b) = [1] 2. weighted path order base order: max/plus interpretations on natural numbers: a#_A(x1) = max{1, x1 - 1} b_A(x1) = x1 precedence: a# = b partial status: pi(a#) = [] pi(b) = [1] The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains.