YES TRS: fac(s(x)) -> *(fac(p(s(x))),s(x)) p(s(0())) -> 0() p(s(s(x))) -> s(p(s(x))) max/plus interpretations on N: fac_A(x1) = max{1, -1} fac#_A(x1) = max{15, 4 + x1} s_A(x1) = max{18, 12 + x1} s#_A(x1) = max{3, 1 + x1} *_A(x1,x2) = max{0, x1, 0} *#_A(x1,x2) = max{0, 14, 0} p_A(x1) = max{10, -8 + x1} p#_A(x1) = max{14, -14 + x1} 0_A = 1 0#_A = 3 precedence: fac > s > * = p > 0