YES We show the termination of the TRS R: *(x,*(minus(y),y)) -> *(minus(*(y,y)),x) -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: *#(x,*(minus(y),y)) -> *#(minus(*(y,y)),x) p2: *#(x,*(minus(y),y)) -> *#(y,y) and R consists of: r1: *(x,*(minus(y),y)) -> *(minus(*(y,y)),x) 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,*(minus(y),y)) -> *#(minus(*(y,y)),x) p2: *#(x,*(minus(y),y)) -> *#(y,y) and R consists of: r1: *(x,*(minus(y),y)) -> *(minus(*(y,y)),x) The set of usable rules consists of r1 Take the reduction pair: lexicographic combination of reduction pairs: 1. matrix interpretations: carrier: N^2 order: standard order interpretations: *#_A(x1,x2) = x1 + x2 *_A(x1,x2) = ((1,0),(1,1)) x1 + ((1,0),(1,1)) x2 + (1,1) minus_A(x1) = ((1,0),(1,0)) x1 + (0,1) 2. matrix interpretations: carrier: N^2 order: standard order interpretations: *#_A(x1,x2) = (0,0) *_A(x1,x2) = ((1,0),(1,1)) x1 + x2 + (1,1) minus_A(x1) = (1,1) 3. matrix interpretations: carrier: N^2 order: standard order interpretations: *#_A(x1,x2) = (0,0) *_A(x1,x2) = ((1,1),(1,0)) x1 + ((1,0),(1,0)) x2 + (1,1) minus_A(x1) = (1,1) The next rules are strictly ordered: p2 We remove them from the problem. -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: *#(x,*(minus(y),y)) -> *#(minus(*(y,y)),x) and R consists of: r1: *(x,*(minus(y),y)) -> *(minus(*(y,y)),x) The estimated dependency graph contains the following SCCs: {p1} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: *#(x,*(minus(y),y)) -> *#(minus(*(y,y)),x) and R consists of: r1: *(x,*(minus(y),y)) -> *(minus(*(y,y)),x) The set of usable rules consists of r1 Take the reduction pair: lexicographic combination of reduction pairs: 1. matrix interpretations: carrier: N^2 order: standard order interpretations: *#_A(x1,x2) = ((0,1),(0,0)) x1 + ((0,1),(0,0)) x2 *_A(x1,x2) = ((1,1),(0,0)) x1 + ((1,1),(0,0)) x2 + (1,2) minus_A(x1) = ((1,1),(0,0)) x1 + (1,1) 2. matrix interpretations: carrier: N^2 order: standard order interpretations: *#_A(x1,x2) = (0,0) *_A(x1,x2) = x1 + x2 + (1,1) minus_A(x1) = (1,1) 3. matrix interpretations: carrier: N^2 order: standard order interpretations: *#_A(x1,x2) = (0,0) *_A(x1,x2) = x2 + (0,1) minus_A(x1) = (1,1) The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains.