MAYBE
TRS:
 {           a__nats() -> cons(0(), incr(nats())),
             a__nats() -> nats(),
            a__pairs() -> cons(0(), incr(odds())),
            a__pairs() -> pairs(),
            a__incr(X) -> incr(X),
  a__incr(cons(X, XS)) -> cons(s(mark(X)), incr(XS)),
             a__odds() -> odds(),
             a__odds() -> a__incr(a__pairs()),
    mark(cons(X1, X2)) -> cons(mark(X1), X2),
             mark(0()) -> 0(),
         mark(incr(X)) -> a__incr(mark(X)),
          mark(nats()) -> a__nats(),
          mark(odds()) -> a__odds(),
            mark(s(X)) -> s(mark(X)),
         mark(pairs()) -> a__pairs(),
         mark(head(X)) -> a__head(mark(X)),
         mark(tail(X)) -> a__tail(mark(X)),
            a__head(X) -> head(X),
  a__head(cons(X, XS)) -> mark(X),
            a__tail(X) -> tail(X),
  a__tail(cons(X, XS)) -> mark(XS)}
 DP:
  Strict:
   {a__incr#(cons(X, XS)) -> mark#(X),
               a__odds#() -> a__pairs#(),
               a__odds#() -> a__incr#(a__pairs()),
      mark#(cons(X1, X2)) -> mark#(X1),
           mark#(incr(X)) -> a__incr#(mark(X)),
           mark#(incr(X)) -> mark#(X),
            mark#(nats()) -> a__nats#(),
            mark#(odds()) -> a__odds#(),
              mark#(s(X)) -> mark#(X),
           mark#(pairs()) -> a__pairs#(),
           mark#(head(X)) -> mark#(X),
           mark#(head(X)) -> a__head#(mark(X)),
           mark#(tail(X)) -> mark#(X),
           mark#(tail(X)) -> a__tail#(mark(X)),
    a__head#(cons(X, XS)) -> mark#(X),
    a__tail#(cons(X, XS)) -> mark#(XS)}
  Weak:
  {           a__nats() -> cons(0(), incr(nats())),
              a__nats() -> nats(),
             a__pairs() -> cons(0(), incr(odds())),
             a__pairs() -> pairs(),
             a__incr(X) -> incr(X),
   a__incr(cons(X, XS)) -> cons(s(mark(X)), incr(XS)),
              a__odds() -> odds(),
              a__odds() -> a__incr(a__pairs()),
     mark(cons(X1, X2)) -> cons(mark(X1), X2),
              mark(0()) -> 0(),
          mark(incr(X)) -> a__incr(mark(X)),
           mark(nats()) -> a__nats(),
           mark(odds()) -> a__odds(),
             mark(s(X)) -> s(mark(X)),
          mark(pairs()) -> a__pairs(),
          mark(head(X)) -> a__head(mark(X)),
          mark(tail(X)) -> a__tail(mark(X)),
             a__head(X) -> head(X),
   a__head(cons(X, XS)) -> mark(X),
             a__tail(X) -> tail(X),
   a__tail(cons(X, XS)) -> mark(XS)}
  EDG:
   {(mark#(incr(X)) -> a__incr#(mark(X)), a__incr#(cons(X, XS)) -> mark#(X))
    (mark#(tail(X)) -> a__tail#(mark(X)), a__tail#(cons(X, XS)) -> mark#(XS))
    (mark#(cons(X1, X2)) -> mark#(X1), mark#(tail(X)) -> a__tail#(mark(X)))
    (mark#(cons(X1, X2)) -> mark#(X1), mark#(tail(X)) -> mark#(X))
    (mark#(cons(X1, X2)) -> mark#(X1), mark#(head(X)) -> a__head#(mark(X)))
    (mark#(cons(X1, X2)) -> mark#(X1), mark#(head(X)) -> mark#(X))
    (mark#(cons(X1, X2)) -> mark#(X1), mark#(pairs()) -> a__pairs#())
    (mark#(cons(X1, X2)) -> mark#(X1), mark#(s(X)) -> mark#(X))
    (mark#(cons(X1, X2)) -> mark#(X1), mark#(odds()) -> a__odds#())
    (mark#(cons(X1, X2)) -> mark#(X1), mark#(nats()) -> a__nats#())
    (mark#(cons(X1, X2)) -> mark#(X1), mark#(incr(X)) -> mark#(X))
    (mark#(cons(X1, X2)) -> mark#(X1), mark#(incr(X)) -> a__incr#(mark(X)))
    (mark#(cons(X1, X2)) -> mark#(X1), mark#(cons(X1, X2)) -> mark#(X1))
    (mark#(incr(X)) -> mark#(X), mark#(tail(X)) -> a__tail#(mark(X)))
    (mark#(incr(X)) -> mark#(X), mark#(tail(X)) -> mark#(X))
    (mark#(incr(X)) -> mark#(X), mark#(head(X)) -> a__head#(mark(X)))
    (mark#(incr(X)) -> mark#(X), mark#(head(X)) -> mark#(X))
    (mark#(incr(X)) -> mark#(X), mark#(pairs()) -> a__pairs#())
    (mark#(incr(X)) -> mark#(X), mark#(s(X)) -> mark#(X))
    (mark#(incr(X)) -> mark#(X), mark#(odds()) -> a__odds#())
    (mark#(incr(X)) -> mark#(X), mark#(nats()) -> a__nats#())
    (mark#(incr(X)) -> mark#(X), mark#(incr(X)) -> mark#(X))
    (mark#(incr(X)) -> mark#(X), mark#(incr(X)) -> a__incr#(mark(X)))
    (mark#(incr(X)) -> mark#(X), mark#(cons(X1, X2)) -> mark#(X1))
    (mark#(head(X)) -> mark#(X), mark#(tail(X)) -> a__tail#(mark(X)))
    (mark#(head(X)) -> mark#(X), mark#(tail(X)) -> mark#(X))
    (mark#(head(X)) -> mark#(X), mark#(head(X)) -> a__head#(mark(X)))
    (mark#(head(X)) -> mark#(X), mark#(head(X)) -> mark#(X))
    (mark#(head(X)) -> mark#(X), mark#(pairs()) -> a__pairs#())
    (mark#(head(X)) -> mark#(X), mark#(s(X)) -> mark#(X))
    (mark#(head(X)) -> mark#(X), mark#(odds()) -> a__odds#())
    (mark#(head(X)) -> mark#(X), mark#(nats()) -> a__nats#())
    (mark#(head(X)) -> mark#(X), mark#(incr(X)) -> mark#(X))
    (mark#(head(X)) -> mark#(X), mark#(incr(X)) -> a__incr#(mark(X)))
    (mark#(head(X)) -> mark#(X), mark#(cons(X1, X2)) -> mark#(X1))
    (a__head#(cons(X, XS)) -> mark#(X), mark#(tail(X)) -> a__tail#(mark(X)))
    (a__head#(cons(X, XS)) -> mark#(X), mark#(tail(X)) -> mark#(X))
    (a__head#(cons(X, XS)) -> mark#(X), mark#(head(X)) -> a__head#(mark(X)))
    (a__head#(cons(X, XS)) -> mark#(X), mark#(head(X)) -> mark#(X))
    (a__head#(cons(X, XS)) -> mark#(X), mark#(pairs()) -> a__pairs#())
    (a__head#(cons(X, XS)) -> mark#(X), mark#(s(X)) -> mark#(X))
    (a__head#(cons(X, XS)) -> mark#(X), mark#(odds()) -> a__odds#())
    (a__head#(cons(X, XS)) -> mark#(X), mark#(nats()) -> a__nats#())
    (a__head#(cons(X, XS)) -> mark#(X), mark#(incr(X)) -> mark#(X))
    (a__head#(cons(X, XS)) -> mark#(X), mark#(incr(X)) -> a__incr#(mark(X)))
    (a__head#(cons(X, XS)) -> mark#(X), mark#(cons(X1, X2)) -> mark#(X1))
    (mark#(tail(X)) -> mark#(X), mark#(cons(X1, X2)) -> mark#(X1))
    (mark#(tail(X)) -> mark#(X), mark#(incr(X)) -> a__incr#(mark(X)))
    (mark#(tail(X)) -> mark#(X), mark#(incr(X)) -> mark#(X))
    (mark#(tail(X)) -> mark#(X), mark#(nats()) -> a__nats#())
    (mark#(tail(X)) -> mark#(X), mark#(odds()) -> a__odds#())
    (mark#(tail(X)) -> mark#(X), mark#(s(X)) -> mark#(X))
    (mark#(tail(X)) -> mark#(X), mark#(pairs()) -> a__pairs#())
    (mark#(tail(X)) -> mark#(X), mark#(head(X)) -> mark#(X))
    (mark#(tail(X)) -> mark#(X), mark#(head(X)) -> a__head#(mark(X)))
    (mark#(tail(X)) -> mark#(X), mark#(tail(X)) -> mark#(X))
    (mark#(tail(X)) -> mark#(X), mark#(tail(X)) -> a__tail#(mark(X)))
    (mark#(s(X)) -> mark#(X), mark#(cons(X1, X2)) -> mark#(X1))
    (mark#(s(X)) -> mark#(X), mark#(incr(X)) -> a__incr#(mark(X)))
    (mark#(s(X)) -> mark#(X), mark#(incr(X)) -> mark#(X))
    (mark#(s(X)) -> mark#(X), mark#(nats()) -> a__nats#())
    (mark#(s(X)) -> mark#(X), mark#(odds()) -> a__odds#())
    (mark#(s(X)) -> mark#(X), mark#(s(X)) -> mark#(X))
    (mark#(s(X)) -> mark#(X), mark#(pairs()) -> a__pairs#())
    (mark#(s(X)) -> mark#(X), mark#(head(X)) -> mark#(X))
    (mark#(s(X)) -> mark#(X), mark#(head(X)) -> a__head#(mark(X)))
    (mark#(s(X)) -> mark#(X), mark#(tail(X)) -> mark#(X))
    (mark#(s(X)) -> mark#(X), mark#(tail(X)) -> a__tail#(mark(X)))
    (a__incr#(cons(X, XS)) -> mark#(X), mark#(cons(X1, X2)) -> mark#(X1))
    (a__incr#(cons(X, XS)) -> mark#(X), mark#(incr(X)) -> a__incr#(mark(X)))
    (a__incr#(cons(X, XS)) -> mark#(X), mark#(incr(X)) -> mark#(X))
    (a__incr#(cons(X, XS)) -> mark#(X), mark#(nats()) -> a__nats#())
    (a__incr#(cons(X, XS)) -> mark#(X), mark#(odds()) -> a__odds#())
    (a__incr#(cons(X, XS)) -> mark#(X), mark#(s(X)) -> mark#(X))
    (a__incr#(cons(X, XS)) -> mark#(X), mark#(pairs()) -> a__pairs#())
    (a__incr#(cons(X, XS)) -> mark#(X), mark#(head(X)) -> mark#(X))
    (a__incr#(cons(X, XS)) -> mark#(X), mark#(head(X)) -> a__head#(mark(X)))
    (a__incr#(cons(X, XS)) -> mark#(X), mark#(tail(X)) -> mark#(X))
    (a__incr#(cons(X, XS)) -> mark#(X), mark#(tail(X)) -> a__tail#(mark(X)))
    (a__odds#() -> a__incr#(a__pairs()), a__incr#(cons(X, XS)) -> mark#(X))
    (mark#(odds()) -> a__odds#(), a__odds#() -> a__pairs#())
    (mark#(odds()) -> a__odds#(), a__odds#() -> a__incr#(a__pairs()))
    (mark#(head(X)) -> a__head#(mark(X)), a__head#(cons(X, XS)) -> mark#(X))
    (a__tail#(cons(X, XS)) -> mark#(XS), mark#(cons(X1, X2)) -> mark#(X1))
    (a__tail#(cons(X, XS)) -> mark#(XS), mark#(incr(X)) -> a__incr#(mark(X)))
    (a__tail#(cons(X, XS)) -> mark#(XS), mark#(incr(X)) -> mark#(X))
    (a__tail#(cons(X, XS)) -> mark#(XS), mark#(nats()) -> a__nats#())
    (a__tail#(cons(X, XS)) -> mark#(XS), mark#(odds()) -> a__odds#())
    (a__tail#(cons(X, XS)) -> mark#(XS), mark#(s(X)) -> mark#(X))
    (a__tail#(cons(X, XS)) -> mark#(XS), mark#(pairs()) -> a__pairs#())
    (a__tail#(cons(X, XS)) -> mark#(XS), mark#(head(X)) -> mark#(X))
    (a__tail#(cons(X, XS)) -> mark#(XS), mark#(head(X)) -> a__head#(mark(X)))
    (a__tail#(cons(X, XS)) -> mark#(XS), mark#(tail(X)) -> mark#(X))
    (a__tail#(cons(X, XS)) -> mark#(XS), mark#(tail(X)) -> a__tail#(mark(X)))}
   SCCS:
    Scc:
     {a__incr#(cons(X, XS)) -> mark#(X),
                 a__odds#() -> a__incr#(a__pairs()),
        mark#(cons(X1, X2)) -> mark#(X1),
             mark#(incr(X)) -> a__incr#(mark(X)),
             mark#(incr(X)) -> mark#(X),
              mark#(odds()) -> a__odds#(),
                mark#(s(X)) -> mark#(X),
             mark#(head(X)) -> mark#(X),
             mark#(head(X)) -> a__head#(mark(X)),
             mark#(tail(X)) -> mark#(X),
             mark#(tail(X)) -> a__tail#(mark(X)),
      a__head#(cons(X, XS)) -> mark#(X),
      a__tail#(cons(X, XS)) -> mark#(XS)}
    SCC:
     Strict:
      {a__incr#(cons(X, XS)) -> mark#(X),
                  a__odds#() -> a__incr#(a__pairs()),
         mark#(cons(X1, X2)) -> mark#(X1),
              mark#(incr(X)) -> a__incr#(mark(X)),
              mark#(incr(X)) -> mark#(X),
               mark#(odds()) -> a__odds#(),
                 mark#(s(X)) -> mark#(X),
              mark#(head(X)) -> mark#(X),
              mark#(head(X)) -> a__head#(mark(X)),
              mark#(tail(X)) -> mark#(X),
              mark#(tail(X)) -> a__tail#(mark(X)),
       a__head#(cons(X, XS)) -> mark#(X),
       a__tail#(cons(X, XS)) -> mark#(XS)}
     Weak:
     {           a__nats() -> cons(0(), incr(nats())),
                 a__nats() -> nats(),
                a__pairs() -> cons(0(), incr(odds())),
                a__pairs() -> pairs(),
                a__incr(X) -> incr(X),
      a__incr(cons(X, XS)) -> cons(s(mark(X)), incr(XS)),
                 a__odds() -> odds(),
                 a__odds() -> a__incr(a__pairs()),
        mark(cons(X1, X2)) -> cons(mark(X1), X2),
                 mark(0()) -> 0(),
             mark(incr(X)) -> a__incr(mark(X)),
              mark(nats()) -> a__nats(),
              mark(odds()) -> a__odds(),
                mark(s(X)) -> s(mark(X)),
             mark(pairs()) -> a__pairs(),
             mark(head(X)) -> a__head(mark(X)),
             mark(tail(X)) -> a__tail(mark(X)),
                a__head(X) -> head(X),
      a__head(cons(X, XS)) -> mark(X),
                a__tail(X) -> tail(X),
      a__tail(cons(X, XS)) -> mark(XS)}
     POLY:
      Argument Filtering:
       pi(tail) = 0, pi(head) = [0], pi(pairs) = [], pi(a__tail#) = 0, pi(a__tail) = 0, pi(a__head#) = 0, pi(a__head) = [0], pi(mark#) = 0, pi(mark) = 0, pi(s) = 0, pi(a__odds#) = [], pi(a__odds) = [], pi(a__incr#) = 0, pi(a__incr) = 0, pi(a__pairs) = [], pi(odds) = [], pi(a__nats) = [], pi(nats) = [], pi(incr) = 0, pi(0) = [], pi(cons) = [0,1]
      Usable Rules:
       {}
      Interpretation:
       [a__odds#] = 0,
       [cons](x0, x1) = x0 + x1,
       [head](x0) = x0 + 1,
       [a__pairs] = 0,
       [odds] = 0
      Strict:
       {a__incr#(cons(X, XS)) -> mark#(X),
                   a__odds#() -> a__incr#(a__pairs()),
          mark#(cons(X1, X2)) -> mark#(X1),
               mark#(incr(X)) -> a__incr#(mark(X)),
               mark#(incr(X)) -> mark#(X),
                mark#(odds()) -> a__odds#(),
                  mark#(s(X)) -> mark#(X),
               mark#(tail(X)) -> mark#(X),
               mark#(tail(X)) -> a__tail#(mark(X)),
        a__head#(cons(X, XS)) -> mark#(X),
        a__tail#(cons(X, XS)) -> mark#(XS)}
      Weak:
       {           a__nats() -> cons(0(), incr(nats())),
                   a__nats() -> nats(),
                  a__pairs() -> cons(0(), incr(odds())),
                  a__pairs() -> pairs(),
                  a__incr(X) -> incr(X),
        a__incr(cons(X, XS)) -> cons(s(mark(X)), incr(XS)),
                   a__odds() -> odds(),
                   a__odds() -> a__incr(a__pairs()),
          mark(cons(X1, X2)) -> cons(mark(X1), X2),
                   mark(0()) -> 0(),
               mark(incr(X)) -> a__incr(mark(X)),
                mark(nats()) -> a__nats(),
                mark(odds()) -> a__odds(),
                  mark(s(X)) -> s(mark(X)),
               mark(pairs()) -> a__pairs(),
               mark(head(X)) -> a__head(mark(X)),
               mark(tail(X)) -> a__tail(mark(X)),
                  a__head(X) -> head(X),
        a__head(cons(X, XS)) -> mark(X),
                  a__tail(X) -> tail(X),
        a__tail(cons(X, XS)) -> mark(XS)}
      EDG:
       {(mark#(incr(X)) -> mark#(X), mark#(tail(X)) -> a__tail#(mark(X)))
        (mark#(incr(X)) -> mark#(X), mark#(tail(X)) -> mark#(X))
        (mark#(incr(X)) -> mark#(X), mark#(s(X)) -> mark#(X))
        (mark#(incr(X)) -> mark#(X), mark#(odds()) -> a__odds#())
        (mark#(incr(X)) -> mark#(X), mark#(incr(X)) -> mark#(X))
        (mark#(incr(X)) -> mark#(X), mark#(incr(X)) -> a__incr#(mark(X)))
        (mark#(incr(X)) -> mark#(X), mark#(cons(X1, X2)) -> mark#(X1))
        (mark#(tail(X)) -> mark#(X), mark#(tail(X)) -> a__tail#(mark(X)))
        (mark#(tail(X)) -> mark#(X), mark#(tail(X)) -> mark#(X))
        (mark#(tail(X)) -> mark#(X), mark#(s(X)) -> mark#(X))
        (mark#(tail(X)) -> mark#(X), mark#(odds()) -> a__odds#())
        (mark#(tail(X)) -> mark#(X), mark#(incr(X)) -> mark#(X))
        (mark#(tail(X)) -> mark#(X), mark#(incr(X)) -> a__incr#(mark(X)))
        (mark#(tail(X)) -> mark#(X), mark#(cons(X1, X2)) -> mark#(X1))
        (a__tail#(cons(X, XS)) -> mark#(XS), mark#(tail(X)) -> a__tail#(mark(X)))
        (a__tail#(cons(X, XS)) -> mark#(XS), mark#(tail(X)) -> mark#(X))
        (a__tail#(cons(X, XS)) -> mark#(XS), mark#(s(X)) -> mark#(X))
        (a__tail#(cons(X, XS)) -> mark#(XS), mark#(odds()) -> a__odds#())
        (a__tail#(cons(X, XS)) -> mark#(XS), mark#(incr(X)) -> mark#(X))
        (a__tail#(cons(X, XS)) -> mark#(XS), mark#(incr(X)) -> a__incr#(mark(X)))
        (a__tail#(cons(X, XS)) -> mark#(XS), mark#(cons(X1, X2)) -> mark#(X1))
        (a__odds#() -> a__incr#(a__pairs()), a__incr#(cons(X, XS)) -> mark#(X))
        (mark#(incr(X)) -> a__incr#(mark(X)), a__incr#(cons(X, XS)) -> mark#(X))
        (mark#(tail(X)) -> a__tail#(mark(X)), a__tail#(cons(X, XS)) -> mark#(XS))
        (mark#(odds()) -> a__odds#(), a__odds#() -> a__incr#(a__pairs()))
        (mark#(cons(X1, X2)) -> mark#(X1), mark#(cons(X1, X2)) -> mark#(X1))
        (mark#(cons(X1, X2)) -> mark#(X1), mark#(incr(X)) -> a__incr#(mark(X)))
        (mark#(cons(X1, X2)) -> mark#(X1), mark#(incr(X)) -> mark#(X))
        (mark#(cons(X1, X2)) -> mark#(X1), mark#(odds()) -> a__odds#())
        (mark#(cons(X1, X2)) -> mark#(X1), mark#(s(X)) -> mark#(X))
        (mark#(cons(X1, X2)) -> mark#(X1), mark#(tail(X)) -> mark#(X))
        (mark#(cons(X1, X2)) -> mark#(X1), mark#(tail(X)) -> a__tail#(mark(X)))
        (a__head#(cons(X, XS)) -> mark#(X), mark#(cons(X1, X2)) -> mark#(X1))
        (a__head#(cons(X, XS)) -> mark#(X), mark#(incr(X)) -> a__incr#(mark(X)))
        (a__head#(cons(X, XS)) -> mark#(X), mark#(incr(X)) -> mark#(X))
        (a__head#(cons(X, XS)) -> mark#(X), mark#(odds()) -> a__odds#())
        (a__head#(cons(X, XS)) -> mark#(X), mark#(s(X)) -> mark#(X))
        (a__head#(cons(X, XS)) -> mark#(X), mark#(tail(X)) -> mark#(X))
        (a__head#(cons(X, XS)) -> mark#(X), mark#(tail(X)) -> a__tail#(mark(X)))
        (mark#(s(X)) -> mark#(X), mark#(cons(X1, X2)) -> mark#(X1))
        (mark#(s(X)) -> mark#(X), mark#(incr(X)) -> a__incr#(mark(X)))
        (mark#(s(X)) -> mark#(X), mark#(incr(X)) -> mark#(X))
        (mark#(s(X)) -> mark#(X), mark#(odds()) -> a__odds#())
        (mark#(s(X)) -> mark#(X), mark#(s(X)) -> mark#(X))
        (mark#(s(X)) -> mark#(X), mark#(tail(X)) -> mark#(X))
        (mark#(s(X)) -> mark#(X), mark#(tail(X)) -> a__tail#(mark(X)))
        (a__incr#(cons(X, XS)) -> mark#(X), mark#(cons(X1, X2)) -> mark#(X1))
        (a__incr#(cons(X, XS)) -> mark#(X), mark#(incr(X)) -> a__incr#(mark(X)))
        (a__incr#(cons(X, XS)) -> mark#(X), mark#(incr(X)) -> mark#(X))
        (a__incr#(cons(X, XS)) -> mark#(X), mark#(odds()) -> a__odds#())
        (a__incr#(cons(X, XS)) -> mark#(X), mark#(s(X)) -> mark#(X))
        (a__incr#(cons(X, XS)) -> mark#(X), mark#(tail(X)) -> mark#(X))
        (a__incr#(cons(X, XS)) -> mark#(X), mark#(tail(X)) -> a__tail#(mark(X)))}
       SCCS:
        Scc:
         {a__incr#(cons(X, XS)) -> mark#(X),
                     a__odds#() -> a__incr#(a__pairs()),
            mark#(cons(X1, X2)) -> mark#(X1),
                 mark#(incr(X)) -> a__incr#(mark(X)),
                 mark#(incr(X)) -> mark#(X),
                  mark#(odds()) -> a__odds#(),
                    mark#(s(X)) -> mark#(X),
                 mark#(tail(X)) -> mark#(X),
                 mark#(tail(X)) -> a__tail#(mark(X)),
          a__tail#(cons(X, XS)) -> mark#(XS)}
        SCC:
         Strict:
          {a__incr#(cons(X, XS)) -> mark#(X),
                      a__odds#() -> a__incr#(a__pairs()),
             mark#(cons(X1, X2)) -> mark#(X1),
                  mark#(incr(X)) -> a__incr#(mark(X)),
                  mark#(incr(X)) -> mark#(X),
                   mark#(odds()) -> a__odds#(),
                     mark#(s(X)) -> mark#(X),
                  mark#(tail(X)) -> mark#(X),
                  mark#(tail(X)) -> a__tail#(mark(X)),
           a__tail#(cons(X, XS)) -> mark#(XS)}
         Weak:
         {           a__nats() -> cons(0(), incr(nats())),
                     a__nats() -> nats(),
                    a__pairs() -> cons(0(), incr(odds())),
                    a__pairs() -> pairs(),
                    a__incr(X) -> incr(X),
          a__incr(cons(X, XS)) -> cons(s(mark(X)), incr(XS)),
                     a__odds() -> odds(),
                     a__odds() -> a__incr(a__pairs()),
            mark(cons(X1, X2)) -> cons(mark(X1), X2),
                     mark(0()) -> 0(),
                 mark(incr(X)) -> a__incr(mark(X)),
                  mark(nats()) -> a__nats(),
                  mark(odds()) -> a__odds(),
                    mark(s(X)) -> s(mark(X)),
                 mark(pairs()) -> a__pairs(),
                 mark(head(X)) -> a__head(mark(X)),
                 mark(tail(X)) -> a__tail(mark(X)),
                    a__head(X) -> head(X),
          a__head(cons(X, XS)) -> mark(X),
                    a__tail(X) -> tail(X),
          a__tail(cons(X, XS)) -> mark(XS)}
         POLY:
          Argument Filtering:
           pi(tail) = [0], pi(head) = 0, pi(pairs) = [], pi(a__tail#) = [0], pi(a__tail) = [0], pi(a__head) = 0, pi(mark#) = [0], pi(mark) = 0, pi(s) = 0, pi(a__odds#) = [], pi(a__odds) = [], pi(a__incr#) = [0], pi(a__incr) = 0, pi(a__pairs) = [], pi(odds) = [], pi(a__nats) = [], pi(nats) = [], pi(incr) = 0, pi(0) = [], pi(cons) = [0,1]
          Usable Rules:
           {}
          Interpretation:
           [a__tail#](x0) = x0 + 1,
           [mark#](x0) = x0 + 1,
           [a__incr#](x0) = x0 + 1,
           [a__odds#] = 1,
           [cons](x0, x1) = x0 + x1,
           [tail](x0) = x0 + 1,
           [a__pairs] = 0,
           [odds] = 0
          Strict:
           {a__incr#(cons(X, XS)) -> mark#(X),
                       a__odds#() -> a__incr#(a__pairs()),
              mark#(cons(X1, X2)) -> mark#(X1),
                   mark#(incr(X)) -> a__incr#(mark(X)),
                   mark#(incr(X)) -> mark#(X),
                    mark#(odds()) -> a__odds#(),
                      mark#(s(X)) -> mark#(X),
            a__tail#(cons(X, XS)) -> mark#(XS)}
          Weak:
           {           a__nats() -> cons(0(), incr(nats())),
                       a__nats() -> nats(),
                      a__pairs() -> cons(0(), incr(odds())),
                      a__pairs() -> pairs(),
                      a__incr(X) -> incr(X),
            a__incr(cons(X, XS)) -> cons(s(mark(X)), incr(XS)),
                       a__odds() -> odds(),
                       a__odds() -> a__incr(a__pairs()),
              mark(cons(X1, X2)) -> cons(mark(X1), X2),
                       mark(0()) -> 0(),
                   mark(incr(X)) -> a__incr(mark(X)),
                    mark(nats()) -> a__nats(),
                    mark(odds()) -> a__odds(),
                      mark(s(X)) -> s(mark(X)),
                   mark(pairs()) -> a__pairs(),
                   mark(head(X)) -> a__head(mark(X)),
                   mark(tail(X)) -> a__tail(mark(X)),
                      a__head(X) -> head(X),
            a__head(cons(X, XS)) -> mark(X),
                      a__tail(X) -> tail(X),
            a__tail(cons(X, XS)) -> mark(XS)}
          EDG:
           {(mark#(incr(X)) -> a__incr#(mark(X)), a__incr#(cons(X, XS)) -> mark#(X))
            (a__odds#() -> a__incr#(a__pairs()), a__incr#(cons(X, XS)) -> mark#(X))
            (mark#(incr(X)) -> mark#(X), mark#(s(X)) -> mark#(X))
            (mark#(incr(X)) -> mark#(X), mark#(odds()) -> a__odds#())
            (mark#(incr(X)) -> mark#(X), mark#(incr(X)) -> mark#(X))
            (mark#(incr(X)) -> mark#(X), mark#(incr(X)) -> a__incr#(mark(X)))
            (mark#(incr(X)) -> mark#(X), mark#(cons(X1, X2)) -> mark#(X1))
            (mark#(cons(X1, X2)) -> mark#(X1), mark#(s(X)) -> mark#(X))
            (mark#(cons(X1, X2)) -> mark#(X1), mark#(odds()) -> a__odds#())
            (mark#(cons(X1, X2)) -> mark#(X1), mark#(incr(X)) -> mark#(X))
            (mark#(cons(X1, X2)) -> mark#(X1), mark#(incr(X)) -> a__incr#(mark(X)))
            (mark#(cons(X1, X2)) -> mark#(X1), mark#(cons(X1, X2)) -> mark#(X1))
            (mark#(s(X)) -> mark#(X), mark#(cons(X1, X2)) -> mark#(X1))
            (mark#(s(X)) -> mark#(X), mark#(incr(X)) -> a__incr#(mark(X)))
            (mark#(s(X)) -> mark#(X), mark#(incr(X)) -> mark#(X))
            (mark#(s(X)) -> mark#(X), mark#(odds()) -> a__odds#())
            (mark#(s(X)) -> mark#(X), mark#(s(X)) -> mark#(X))
            (a__incr#(cons(X, XS)) -> mark#(X), mark#(cons(X1, X2)) -> mark#(X1))
            (a__incr#(cons(X, XS)) -> mark#(X), mark#(incr(X)) -> a__incr#(mark(X)))
            (a__incr#(cons(X, XS)) -> mark#(X), mark#(incr(X)) -> mark#(X))
            (a__incr#(cons(X, XS)) -> mark#(X), mark#(odds()) -> a__odds#())
            (a__incr#(cons(X, XS)) -> mark#(X), mark#(s(X)) -> mark#(X))
            (mark#(odds()) -> a__odds#(), a__odds#() -> a__incr#(a__pairs()))
            (a__tail#(cons(X, XS)) -> mark#(XS), mark#(cons(X1, X2)) -> mark#(X1))
            (a__tail#(cons(X, XS)) -> mark#(XS), mark#(incr(X)) -> a__incr#(mark(X)))
            (a__tail#(cons(X, XS)) -> mark#(XS), mark#(incr(X)) -> mark#(X))
            (a__tail#(cons(X, XS)) -> mark#(XS), mark#(odds()) -> a__odds#())
            (a__tail#(cons(X, XS)) -> mark#(XS), mark#(s(X)) -> mark#(X))}
           SCCS:
            Scc:
             {a__incr#(cons(X, XS)) -> mark#(X),
                         a__odds#() -> a__incr#(a__pairs()),
                mark#(cons(X1, X2)) -> mark#(X1),
                     mark#(incr(X)) -> a__incr#(mark(X)),
                     mark#(incr(X)) -> mark#(X),
                      mark#(odds()) -> a__odds#(),
                        mark#(s(X)) -> mark#(X)}
            SCC:
             Strict:
              {a__incr#(cons(X, XS)) -> mark#(X),
                          a__odds#() -> a__incr#(a__pairs()),
                 mark#(cons(X1, X2)) -> mark#(X1),
                      mark#(incr(X)) -> a__incr#(mark(X)),
                      mark#(incr(X)) -> mark#(X),
                       mark#(odds()) -> a__odds#(),
                         mark#(s(X)) -> mark#(X)}
             Weak:
             {           a__nats() -> cons(0(), incr(nats())),
                         a__nats() -> nats(),
                        a__pairs() -> cons(0(), incr(odds())),
                        a__pairs() -> pairs(),
                        a__incr(X) -> incr(X),
              a__incr(cons(X, XS)) -> cons(s(mark(X)), incr(XS)),
                         a__odds() -> odds(),
                         a__odds() -> a__incr(a__pairs()),
                mark(cons(X1, X2)) -> cons(mark(X1), X2),
                         mark(0()) -> 0(),
                     mark(incr(X)) -> a__incr(mark(X)),
                      mark(nats()) -> a__nats(),
                      mark(odds()) -> a__odds(),
                        mark(s(X)) -> s(mark(X)),
                     mark(pairs()) -> a__pairs(),
                     mark(head(X)) -> a__head(mark(X)),
                     mark(tail(X)) -> a__tail(mark(X)),
                        a__head(X) -> head(X),
              a__head(cons(X, XS)) -> mark(X),
                        a__tail(X) -> tail(X),
              a__tail(cons(X, XS)) -> mark(XS)}
             Fail