proposition: Lemma prodrMn_const n (I : finType) (A : pred I) (F : I -> R) : \prod_(i in A) (F i *+ n) = \prod_(i in A) F i *+ n ^ #|A|.
proof: Proof. by rewrite prodrMn prod_nat_const. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat div seq) mathcomp(choice fintype finfun bigop prime binomial)