MAYBE We are left with following problem, upon which TcT provides the certificate MAYBE. Strict Trs: { primes() -> sieve(from(s(s(0())))) , sieve(X) -> n__sieve(X) , sieve(cons(X, Y)) -> cons(X, n__filter(X, n__sieve(activate(Y)))) , from(X) -> cons(X, n__from(n__s(X))) , from(X) -> n__from(X) , s(X) -> n__s(X) , cons(X1, X2) -> n__cons(X1, X2) , head(cons(X, Y)) -> X , tail(cons(X, Y)) -> activate(Y) , activate(X) -> X , activate(n__from(X)) -> from(activate(X)) , activate(n__s(X)) -> s(activate(X)) , activate(n__filter(X1, X2)) -> filter(activate(X1), activate(X2)) , activate(n__cons(X1, X2)) -> cons(activate(X1), X2) , activate(n__sieve(X)) -> sieve(activate(X)) , if(true(), X, Y) -> activate(X) , if(false(), X, Y) -> activate(Y) , filter(X1, X2) -> n__filter(X1, X2) , filter(s(s(X)), cons(Y, Z)) -> if(divides(s(s(X)), Y), n__filter(n__s(n__s(X)), activate(Z)), n__cons(Y, n__filter(X, n__sieve(Y)))) } Obligation: runtime complexity Answer: MAYBE None of the processors succeeded. Details of failed attempt(s): ----------------------------- 1) 'WithProblem (timeout of 60 seconds)' failed due to the following reason: Computation stopped due to timeout after 60.0 seconds. 2) 'Best' failed due to the following reason: None of the processors succeeded. Details of failed attempt(s): ----------------------------- 1) 'WithProblem (timeout of 30 seconds) (timeout of 60 seconds)' failed due to the following reason: Computation stopped due to timeout after 30.0 seconds. 2) 'Best' failed due to the following reason: None of the processors succeeded. Details of failed attempt(s): ----------------------------- 1) 'Polynomial Path Order (PS) (timeout of 60 seconds)' failed due to the following reason: The processor is inapplicable, reason: Processor only applicable for innermost runtime complexity analysis 2) 'bsearch-popstar (timeout of 60 seconds)' failed due to the following reason: The processor is inapplicable, reason: Processor only applicable for innermost runtime complexity analysis 3) 'Fastest (timeout of 5 seconds) (timeout of 60 seconds)' failed due to the following reason: None of the processors succeeded. Details of failed attempt(s): ----------------------------- 1) 'Bounds with perSymbol-enrichment and initial automaton 'match'' failed due to the following reason: match-boundness of the problem could not be verified. 2) 'Bounds with minimal-enrichment and initial automaton 'match'' failed due to the following reason: match-boundness of the problem could not be verified. 3) 'Innermost Weak Dependency Pairs (timeout of 60 seconds)' failed due to the following reason: We add the following weak dependency pairs: Strict DPs: { primes^#() -> c_1(sieve^#(from(s(s(0()))))) , sieve^#(X) -> c_2(X) , sieve^#(cons(X, Y)) -> c_3(cons^#(X, n__filter(X, n__sieve(activate(Y))))) , cons^#(X1, X2) -> c_7(X1, X2) , from^#(X) -> c_4(cons^#(X, n__from(n__s(X)))) , from^#(X) -> c_5(X) , s^#(X) -> c_6(X) , head^#(cons(X, Y)) -> c_8(X) , tail^#(cons(X, Y)) -> c_9(activate^#(Y)) , activate^#(X) -> c_10(X) , activate^#(n__from(X)) -> c_11(from^#(activate(X))) , activate^#(n__s(X)) -> c_12(s^#(activate(X))) , activate^#(n__filter(X1, X2)) -> c_13(filter^#(activate(X1), activate(X2))) , activate^#(n__cons(X1, X2)) -> c_14(cons^#(activate(X1), X2)) , activate^#(n__sieve(X)) -> c_15(sieve^#(activate(X))) , filter^#(X1, X2) -> c_18(X1, X2) , filter^#(s(s(X)), cons(Y, Z)) -> c_19(if^#(divides(s(s(X)), Y), n__filter(n__s(n__s(X)), activate(Z)), n__cons(Y, n__filter(X, n__sieve(Y))))) , if^#(true(), X, Y) -> c_16(activate^#(X)) , if^#(false(), X, Y) -> c_17(activate^#(Y)) } and mark the set of starting terms. We are left with following problem, upon which TcT provides the certificate MAYBE. Strict DPs: { primes^#() -> c_1(sieve^#(from(s(s(0()))))) , sieve^#(X) -> c_2(X) , sieve^#(cons(X, Y)) -> c_3(cons^#(X, n__filter(X, n__sieve(activate(Y))))) , cons^#(X1, X2) -> c_7(X1, X2) , from^#(X) -> c_4(cons^#(X, n__from(n__s(X)))) , from^#(X) -> c_5(X) , s^#(X) -> c_6(X) , head^#(cons(X, Y)) -> c_8(X) , tail^#(cons(X, Y)) -> c_9(activate^#(Y)) , activate^#(X) -> c_10(X) , activate^#(n__from(X)) -> c_11(from^#(activate(X))) , activate^#(n__s(X)) -> c_12(s^#(activate(X))) , activate^#(n__filter(X1, X2)) -> c_13(filter^#(activate(X1), activate(X2))) , activate^#(n__cons(X1, X2)) -> c_14(cons^#(activate(X1), X2)) , activate^#(n__sieve(X)) -> c_15(sieve^#(activate(X))) , filter^#(X1, X2) -> c_18(X1, X2) , filter^#(s(s(X)), cons(Y, Z)) -> c_19(if^#(divides(s(s(X)), Y), n__filter(n__s(n__s(X)), activate(Z)), n__cons(Y, n__filter(X, n__sieve(Y))))) , if^#(true(), X, Y) -> c_16(activate^#(X)) , if^#(false(), X, Y) -> c_17(activate^#(Y)) } Strict Trs: { primes() -> sieve(from(s(s(0())))) , sieve(X) -> n__sieve(X) , sieve(cons(X, Y)) -> cons(X, n__filter(X, n__sieve(activate(Y)))) , from(X) -> cons(X, n__from(n__s(X))) , from(X) -> n__from(X) , s(X) -> n__s(X) , cons(X1, X2) -> n__cons(X1, X2) , head(cons(X, Y)) -> X , tail(cons(X, Y)) -> activate(Y) , activate(X) -> X , activate(n__from(X)) -> from(activate(X)) , activate(n__s(X)) -> s(activate(X)) , activate(n__filter(X1, X2)) -> filter(activate(X1), activate(X2)) , activate(n__cons(X1, X2)) -> cons(activate(X1), X2) , activate(n__sieve(X)) -> sieve(activate(X)) , if(true(), X, Y) -> activate(X) , if(false(), X, Y) -> activate(Y) , filter(X1, X2) -> n__filter(X1, X2) , filter(s(s(X)), cons(Y, Z)) -> if(divides(s(s(X)), Y), n__filter(n__s(n__s(X)), activate(Z)), n__cons(Y, n__filter(X, n__sieve(Y)))) } Obligation: runtime complexity Answer: MAYBE We estimate the number of application of {17} by applications of Pre({17}) = {2,4,6,7,8,10,13,16}. Here rules are labeled as follows: DPs: { 1: primes^#() -> c_1(sieve^#(from(s(s(0()))))) , 2: sieve^#(X) -> c_2(X) , 3: sieve^#(cons(X, Y)) -> c_3(cons^#(X, n__filter(X, n__sieve(activate(Y))))) , 4: cons^#(X1, X2) -> c_7(X1, X2) , 5: from^#(X) -> c_4(cons^#(X, n__from(n__s(X)))) , 6: from^#(X) -> c_5(X) , 7: s^#(X) -> c_6(X) , 8: head^#(cons(X, Y)) -> c_8(X) , 9: tail^#(cons(X, Y)) -> c_9(activate^#(Y)) , 10: activate^#(X) -> c_10(X) , 11: activate^#(n__from(X)) -> c_11(from^#(activate(X))) , 12: activate^#(n__s(X)) -> c_12(s^#(activate(X))) , 13: activate^#(n__filter(X1, X2)) -> c_13(filter^#(activate(X1), activate(X2))) , 14: activate^#(n__cons(X1, X2)) -> c_14(cons^#(activate(X1), X2)) , 15: activate^#(n__sieve(X)) -> c_15(sieve^#(activate(X))) , 16: filter^#(X1, X2) -> c_18(X1, X2) , 17: filter^#(s(s(X)), cons(Y, Z)) -> c_19(if^#(divides(s(s(X)), Y), n__filter(n__s(n__s(X)), activate(Z)), n__cons(Y, n__filter(X, n__sieve(Y))))) , 18: if^#(true(), X, Y) -> c_16(activate^#(X)) , 19: if^#(false(), X, Y) -> c_17(activate^#(Y)) } We are left with following problem, upon which TcT provides the certificate MAYBE. Strict DPs: { primes^#() -> c_1(sieve^#(from(s(s(0()))))) , sieve^#(X) -> c_2(X) , sieve^#(cons(X, Y)) -> c_3(cons^#(X, n__filter(X, n__sieve(activate(Y))))) , cons^#(X1, X2) -> c_7(X1, X2) , from^#(X) -> c_4(cons^#(X, n__from(n__s(X)))) , from^#(X) -> c_5(X) , s^#(X) -> c_6(X) , head^#(cons(X, Y)) -> c_8(X) , tail^#(cons(X, Y)) -> c_9(activate^#(Y)) , activate^#(X) -> c_10(X) , activate^#(n__from(X)) -> c_11(from^#(activate(X))) , activate^#(n__s(X)) -> c_12(s^#(activate(X))) , activate^#(n__filter(X1, X2)) -> c_13(filter^#(activate(X1), activate(X2))) , activate^#(n__cons(X1, X2)) -> c_14(cons^#(activate(X1), X2)) , activate^#(n__sieve(X)) -> c_15(sieve^#(activate(X))) , filter^#(X1, X2) -> c_18(X1, X2) , if^#(true(), X, Y) -> c_16(activate^#(X)) , if^#(false(), X, Y) -> c_17(activate^#(Y)) } Strict Trs: { primes() -> sieve(from(s(s(0())))) , sieve(X) -> n__sieve(X) , sieve(cons(X, Y)) -> cons(X, n__filter(X, n__sieve(activate(Y)))) , from(X) -> cons(X, n__from(n__s(X))) , from(X) -> n__from(X) , s(X) -> n__s(X) , cons(X1, X2) -> n__cons(X1, X2) , head(cons(X, Y)) -> X , tail(cons(X, Y)) -> activate(Y) , activate(X) -> X , activate(n__from(X)) -> from(activate(X)) , activate(n__s(X)) -> s(activate(X)) , activate(n__filter(X1, X2)) -> filter(activate(X1), activate(X2)) , activate(n__cons(X1, X2)) -> cons(activate(X1), X2) , activate(n__sieve(X)) -> sieve(activate(X)) , if(true(), X, Y) -> activate(X) , if(false(), X, Y) -> activate(Y) , filter(X1, X2) -> n__filter(X1, X2) , filter(s(s(X)), cons(Y, Z)) -> if(divides(s(s(X)), Y), n__filter(n__s(n__s(X)), activate(Z)), n__cons(Y, n__filter(X, n__sieve(Y)))) } Weak DPs: { filter^#(s(s(X)), cons(Y, Z)) -> c_19(if^#(divides(s(s(X)), Y), n__filter(n__s(n__s(X)), activate(Z)), n__cons(Y, n__filter(X, n__sieve(Y))))) } Obligation: runtime complexity Answer: MAYBE Empty strict component of the problem is NOT empty. Arrrr..