WORST_CASE(?,O(n^1))

Solution:
---------

  * :: [A(0) x A(15)] -(1)-> A(0)
  + :: [A(15) x A(15)] -(15)-> A(15)
  + :: [A(0) x A(0)] -(0)-> A(0)


Cost Free Signatures:
---------------------

  * :: [A_cf(0) x A_cf(0)] -(0)-> A_cf(0)
  + :: [A_cf(0) x A_cf(0)] -(0)-> A_cf(0)


Base Constructors:
------------------
  +_A :: [A(0) x A(0)] -(0)-> A(0)