YES linear polynomial interpretations on negative integers: power_A(x1,x2) = 0 mult_A(x1,x2) = x1 s_A(x1) = 0 0_A = -1 div_A(x1,x2) = x1 mod_A(x1,x2) = x1 minus_A(x1,x2) = x1 lte_A(x1,x2) = x1 false_A = 0 true_A = -1 add_A(x1,x2) = 0 the condition mod(0(),s(s(0()))) ->> s(x1) is unsatisfiable for all substitutions.