proposition: Lemma revrX x n : (x : R^c) ^+ n = (x : R) ^+ n.
proof: Proof. by elim: n => // n IHn; rewrite exprS exprSr IHn. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat div seq) mathcomp(choice fintype finfun bigop prime binomial)