TIMEOUT We are left with following problem, upon which TcT provides the certificate TIMEOUT. Strict Trs: { ackin(s(X), s(Y)) -> u21(ackin(s(X), Y), X) , u21(ackout(X), Y) -> u22(ackin(Y, X)) } Obligation: innermost runtime complexity Answer: TIMEOUT Computation stopped due to timeout after 10.0 seconds. Arrrr..