YES We show the termination of the TRS R: .(.(x,y),z) -> .(x,.(y,z)) -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: .#(.(x,y),z) -> .#(x,.(y,z)) p2: .#(.(x,y),z) -> .#(y,z) and R consists of: r1: .(.(x,y),z) -> .(x,.(y,z)) The estimated dependency graph contains the following SCCs: {p1, p2} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: .#(.(x,y),z) -> .#(x,.(y,z)) p2: .#(.(x,y),z) -> .#(y,z) and R consists of: r1: .(.(x,y),z) -> .(x,.(y,z)) The set of usable rules consists of r1 Take the reduction pair: lexicographic combination of reduction pairs: 1. weighted path order base order: max/plus interpretations on natural numbers: .#_A(x1,x2) = x1 + 4 ._A(x1,x2) = max{x1 + 5, x2} precedence: .# = . partial status: pi(.#) = [] pi(.) = [] 2. weighted path order base order: max/plus interpretations on natural numbers: .#_A(x1,x2) = 0 ._A(x1,x2) = 2 precedence: . > .# partial status: pi(.#) = [] pi(.) = [] The next rules are strictly ordered: p1 We remove them from the problem. -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: .#(.(x,y),z) -> .#(y,z) and R consists of: r1: .(.(x,y),z) -> .(x,.(y,z)) The estimated dependency graph contains the following SCCs: {p1} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: .#(.(x,y),z) -> .#(y,z) and R consists of: r1: .(.(x,y),z) -> .(x,.(y,z)) 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(x1,x2) = max{x1 + 1, x2} ._A(x1,x2) = max{x1 - 1, x2} precedence: .# = . partial status: pi(.#) = [1, 2] pi(.) = [2] 2. weighted path order base order: max/plus interpretations on natural numbers: .#_A(x1,x2) = max{x1 - 1, x2 + 1} ._A(x1,x2) = x2 precedence: .# = . partial status: pi(.#) = [] pi(.) = [2] The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains.