YES We show the termination of the relative TRS R/S: R: f(g(x)) -> g(f(f(x))) f(h(x)) -> h(g(x)) |f'|(s(x),y,y) -> |f'|(y,x,s(x)) S: rand(x) -> x rand(x) -> rand(s(x)) -- SCC decomposition. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: f#(g(x)) -> f#(f(x)) p2: f#(g(x)) -> f#(x) p3: |f'|#(s(x),y,y) -> |f'|#(y,x,s(x)) and R consists of: r1: f(g(x)) -> g(f(f(x))) r2: f(h(x)) -> h(g(x)) r3: |f'|(s(x),y,y) -> |f'|(y,x,s(x)) r4: rand(x) -> x r5: rand(x) -> rand(s(x)) The estimated dependency graph contains the following SCCs: {p1, p2} {p3} -- Reduction pair. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: f#(g(x)) -> f#(f(x)) p2: f#(g(x)) -> f#(x) and R consists of: r1: f(g(x)) -> g(f(f(x))) r2: f(h(x)) -> h(g(x)) r3: |f'|(s(x),y,y) -> |f'|(y,x,s(x)) r4: rand(x) -> x r5: rand(x) -> rand(s(x)) The set of usable rules consists of r1, r2, r3, r4, r5 Take the reduction pair: lexicographic combination of reduction pairs: 1. weighted path order base order: max/plus interpretations on natural numbers: f#_A(x1) = x1 + 2 g_A(x1) = x1 f_A(x1) = x1 h_A(x1) = x1 + 2 |f'|_A(x1,x2,x3) = 1 s_A(x1) = 0 rand_A(x1) = x1 precedence: f# = g = f = h = |f'| = s = rand partial status: pi(f#) = [] pi(g) = [] pi(f) = [] pi(h) = [] pi(|f'|) = [] pi(s) = [] pi(rand) = [] 2. weighted path order base order: max/plus interpretations on natural numbers: f#_A(x1) = max{5, x1 + 4} g_A(x1) = x1 + 3 f_A(x1) = x1 h_A(x1) = 3 |f'|_A(x1,x2,x3) = 1 s_A(x1) = 0 rand_A(x1) = x1 precedence: f# = g = f = h = |f'| = s = rand partial status: pi(f#) = [] pi(g) = [] pi(f) = [] pi(h) = [] pi(|f'|) = [] pi(s) = [] pi(rand) = [] The next rules are strictly ordered: p1 We remove them from the problem. -- SCC decomposition. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: f#(g(x)) -> f#(x) and R consists of: r1: f(g(x)) -> g(f(f(x))) r2: f(h(x)) -> h(g(x)) r3: |f'|(s(x),y,y) -> |f'|(y,x,s(x)) r4: rand(x) -> x r5: rand(x) -> rand(s(x)) The estimated dependency graph contains the following SCCs: {p1} -- Reduction pair. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: f#(g(x)) -> f#(x) and R consists of: r1: f(g(x)) -> g(f(f(x))) r2: f(h(x)) -> h(g(x)) r3: |f'|(s(x),y,y) -> |f'|(y,x,s(x)) r4: rand(x) -> x r5: rand(x) -> rand(s(x)) The set of usable rules consists of r1, r2, r3, r4, r5 Take the reduction pair: lexicographic combination of reduction pairs: 1. weighted path order base order: max/plus interpretations on natural numbers: f#_A(x1) = max{4, x1 + 1} g_A(x1) = max{5, x1 + 2} f_A(x1) = max{3, x1} h_A(x1) = 3 |f'|_A(x1,x2,x3) = max{x1 + 4, x3 + 5} s_A(x1) = 0 rand_A(x1) = x1 + 1 precedence: f > f# = g = h = |f'| = s = rand partial status: pi(f#) = [1] pi(g) = [1] pi(f) = [1] pi(h) = [] pi(|f'|) = [] pi(s) = [] pi(rand) = [] 2. weighted path order base order: max/plus interpretations on natural numbers: f#_A(x1) = max{1, x1} g_A(x1) = max{6, x1 + 2} f_A(x1) = max{3, x1} h_A(x1) = 6 |f'|_A(x1,x2,x3) = 1 s_A(x1) = 2 rand_A(x1) = 0 precedence: f# = g = f = h = |f'| = s = rand partial status: pi(f#) = [1] pi(g) = [1] pi(f) = [1] pi(h) = [] pi(|f'|) = [] pi(s) = [] pi(rand) = [] The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains. -- Reduction pair. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: |f'|#(s(x),y,y) -> |f'|#(y,x,s(x)) and R consists of: r1: f(g(x)) -> g(f(f(x))) r2: f(h(x)) -> h(g(x)) r3: |f'|(s(x),y,y) -> |f'|(y,x,s(x)) r4: rand(x) -> x r5: rand(x) -> rand(s(x)) The set of usable rules consists of r1, r2, r3, r4, r5 Take the reduction pair: lexicographic combination of reduction pairs: 1. weighted path order base order: matrix interpretations: carrier: N^2 order: lexicographic order interpretations: |f'|#_A(x1,x2,x3) = x1 + ((1,0),(1,1)) x2 s_A(x1) = ((1,0),(1,1)) x1 + (0,2) f_A(x1) = (3,2) g_A(x1) = (1,0) h_A(x1) = (2,1) |f'|_A(x1,x2,x3) = ((0,0),(1,0)) x1 + ((0,0),(1,0)) x3 + (1,1) rand_A(x1) = ((1,0),(0,0)) x1 + (1,3) precedence: |f'|# = s = f = g = h = |f'| = rand partial status: pi(|f'|#) = [] pi(s) = [] pi(f) = [] pi(g) = [] pi(h) = [] pi(|f'|) = [] pi(rand) = [] 2. weighted path order base order: matrix interpretations: carrier: N^2 order: lexicographic order interpretations: |f'|#_A(x1,x2,x3) = ((1,0),(1,1)) x1 + ((1,0),(1,1)) x2 + (2,2) s_A(x1) = ((1,0),(1,1)) x1 + (1,1) f_A(x1) = (2,1) g_A(x1) = (3,2) h_A(x1) = (1,3) |f'|_A(x1,x2,x3) = (0,0) rand_A(x1) = (2,2) precedence: s = f = g = h = rand > |f'|# = |f'| partial status: pi(|f'|#) = [1, 2] pi(s) = [] pi(f) = [] pi(g) = [] pi(h) = [] pi(|f'|) = [] pi(rand) = [] The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains.