fact: Fixpoint sub_list l k n : list A := match l, k, n with | _ :: l', S k', _ => sub_list l' k' n | x :: l', 0, S n' => x :: sub_list l' 0 n' | _, _, _ => nil end.
imports: CoLoR(LogicUtil EqUtil RelUtil BoolUtil NatUtil) Coq(Setoid SetoidList FunInd)