proposition: Lemma dvdrP a b : reflect (exists x, b = x * a) (a %| b).
proof: Proof. rewrite /dvdr; case: odivrP=> //= [x|] hx; constructor; first by exists x. by case=> x /eqP; apply: negP. Qed.
imports: HB(structures) Coq(ssreflect ssrfun ssrbool Arith.Wf_nat) mathcomp(eqtype ssrnat div seq path) mathcomp(ssralg fintype perm tuple choice generic_quotient) mathcomp(matrix bigop zmodp mxalgebra poly) stronglydiscrete