fact: Definition icons3 (a : A) {n} {l : Vector.t A n} (b : B a) (il : ilist3 l) : ilist3 (a :: l) := {| prim_fst := b; prim_snd := il |}.
imports: Coq.Lists.List Coq.Strings.String Coq.Arith.Arith Fiat.Common.ilist Fiat.Common