MAYBE
* Step 1: Failure MAYBE
  + Considered Problem:
      - Strict TRS:
          a__filter(X1,X2) -> filter(X1,X2)
          a__filter(s(s(X)),cons(Y,Z)) -> a__if(divides(s(s(mark(X))),mark(Y))
                                               ,filter(s(s(X)),Z)
                                               ,cons(Y,filter(X,sieve(Y))))
          a__from(X) -> cons(mark(X),from(s(X)))
          a__from(X) -> from(X)
          a__head(X) -> head(X)
          a__head(cons(X,Y)) -> mark(X)
          a__if(X1,X2,X3) -> if(X1,X2,X3)
          a__if(false(),X,Y) -> mark(Y)
          a__if(true(),X,Y) -> mark(X)
          a__primes() -> a__sieve(a__from(s(s(0()))))
          a__primes() -> primes()
          a__sieve(X) -> sieve(X)
          a__sieve(cons(X,Y)) -> cons(mark(X),filter(X,sieve(Y)))
          a__tail(X) -> tail(X)
          a__tail(cons(X,Y)) -> mark(Y)
          mark(0()) -> 0()
          mark(cons(X1,X2)) -> cons(mark(X1),X2)
          mark(divides(X1,X2)) -> divides(mark(X1),mark(X2))
          mark(false()) -> false()
          mark(filter(X1,X2)) -> a__filter(mark(X1),mark(X2))
          mark(from(X)) -> a__from(mark(X))
          mark(head(X)) -> a__head(mark(X))
          mark(if(X1,X2,X3)) -> a__if(mark(X1),X2,X3)
          mark(primes()) -> a__primes()
          mark(s(X)) -> s(mark(X))
          mark(sieve(X)) -> a__sieve(mark(X))
          mark(tail(X)) -> a__tail(mark(X))
          mark(true()) -> true()
      - Signature:
          {a__filter/2,a__from/1,a__head/1,a__if/3,a__primes/0,a__sieve/1,a__tail/1,mark/1} / {0/0,cons/2,divides/2
          ,false/0,filter/2,from/1,head/1,if/3,primes/0,s/1,sieve/1,tail/1,true/0}
      - Obligation:
          innermost runtime complexity wrt. defined symbols {a__filter,a__from,a__head,a__if,a__primes,a__sieve
          ,a__tail,mark} and constructors {0,cons,divides,false,filter,from,head,if,primes,s,sieve,tail,true}
  + Applied Processor:
      Ara {heuristics_ = NoHeuristics, minDegree = 1, maxDegree = 3, araTimeout = 60, araFindStrictRules = Nothing, araSmtSolver = MiniSMT}
  + Details:
      The input can not be schown compatible.
MAYBE