YES(O(1),O(n^1)) We are left with following problem, upon which TcT provides the certificate YES(O(1),O(n^1)). Strict Trs: { prime(0()) -> false() , prime(s(0())) -> false() , prime(s(s(x))) -> prime1(s(s(x)), s(x)) , prime1(x, 0()) -> false() , prime1(x, s(0())) -> true() , prime1(x, s(s(y))) -> and(not(divp(s(s(y)), x)), prime1(x, s(y))) , divp(x, y) -> =(rem(x, y), 0()) } Obligation: innermost runtime complexity Answer: YES(O(1),O(n^1)) We use the processor 'Small Polynomial Path Order (PS,1-bounded)' to orient following rules strictly. Trs: { prime(0()) -> false() , prime(s(0())) -> false() , prime(s(s(x))) -> prime1(s(s(x)), s(x)) , prime1(x, 0()) -> false() , prime1(x, s(0())) -> true() , prime1(x, s(s(y))) -> and(not(divp(s(s(y)), x)), prime1(x, s(y))) , divp(x, y) -> =(rem(x, y), 0()) } The induced complexity on above rules (modulo remaining rules) is YES(?,O(n^1)) . These rules are moved into the corresponding weak component(s). Sub-proof: ---------- The input was oriented with the instance of 'Small Polynomial Path Order (PS,1-bounded)' as induced by the safe mapping safe(prime) = {}, safe(0) = {}, safe(false) = {}, safe(s) = {1}, safe(prime1) = {1}, safe(true) = {}, safe(and) = {1, 2}, safe(not) = {1}, safe(divp) = {1, 2}, safe(=) = {1, 2}, safe(rem) = {1, 2} and precedence prime > prime1, prime > divp, prime1 > divp . Following symbols are considered recursive: {prime1} The recursion depth is 1. For your convenience, here are the satisfied ordering constraints: prime(0();) > false() prime(s(; 0());) > false() prime(s(; s(; x));) > prime1(s(; x); s(; s(; x))) prime1(0(); x) > false() prime1(s(; 0()); x) > true() prime1(s(; s(; y)); x) > and(; not(; divp(; s(; s(; y)), x)), prime1(s(; y); x)) divp(; x, y) > =(; rem(; x, y), 0()) We return to the main proof. We are left with following problem, upon which TcT provides the certificate YES(O(1),O(1)). Weak Trs: { prime(0()) -> false() , prime(s(0())) -> false() , prime(s(s(x))) -> prime1(s(s(x)), s(x)) , prime1(x, 0()) -> false() , prime1(x, s(0())) -> true() , prime1(x, s(s(y))) -> and(not(divp(s(s(y)), x)), prime1(x, s(y))) , divp(x, y) -> =(rem(x, y), 0()) } Obligation: innermost runtime complexity Answer: YES(O(1),O(1)) Empty rules are trivially bounded Hurray, we answered YES(O(1),O(n^1))