YES TRS: sum(0()) -> 0() sum(s(x)) -> +(sqr(s(x)),sum(x)) sqr(x) -> *(x,x) sum(s(x)) -> +(*(s(x),s(x)),sum(x)) max/plus interpretations on N: sum_A(x1) = max{7, 4 + x1} sum#_A(x1) = max{7, 4 + x1} 0_A = 0 0#_A = 0 s_A(x1) = max{1, 5 + x1} s#_A(x1) = max{1, 5 + x1} +_A(x1,x2) = max{0, 2 + x1, 1 + x2} +#_A(x1,x2) = max{0, 2 + x1, 1 + x2} sqr_A(x1) = max{6, 1 + x1} sqr#_A(x1) = max{6, 1 + x1} *_A(x1,x2) = max{6, x1, x2} *#_A(x1,x2) = max{6, x1, x2} precedence: sqr > sum > 0 = s = + = *