proposition: Lemma dvdp_exp2l d k l : k <= l -> d ^+ k %| d ^+ l.
proof: Proof. by move/subnK <-; rewrite exprD dvdp_mull // ?lead_coef_exp ?unitrX. Qed.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(fintype bigop ssralg poly)