proposition: Lemma size_set_nth p n val : size (set_nth p n val) = maxn n.+1 (size p).
proof: Proof. by rewrite /size seq.size_set_nth. Qed.
imports: Coq(ZArith Reals) Coquelicot(Coquelicot) mathcomp.ssreflect(ssreflect ssrfun ssrbool eqtype ssrnat seq fintype bigop) Flocq(Core) Stdlib MathComp Interval Xreal Basic_rec