A Syntactic Operator for Forgetting that Satisfies Strong Persistence
  Whereas the operation of forgetting has recently seen a considerable amount
of attention in the context of Answer Set Programming (ASP), most of it has
focused on theoretical aspects, leaving the practical issues largely untouched.
Recent studies include results about what sets of properties operators should
satisfy, as well as the abstract characterization of several operators and
their theoretical limits. However, no concrete operators have been
investigated.
  In this paper, we address this issue by presenting the first concrete
operator that satisfies strong persistence - a property that seems to best
capture the essence of forgetting in the context of ASP - whenever this is
possible, and many other important properties. The operator is syntactic,
limiting the computation of the forgetting result to manipulating the rules in
which the atoms to be forgotten occur, naturally yielding a forgetting result
that is close to the original program.
  This paper is under consideration for acceptance in TPLP.
