proposition: Lemma sdvdr_def : forall a b, a %<| b = (a %| b) && ~~(b %| a).
proof: Proof. by []. 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