proposition: Lemma dot_neg_surj {Hl: BL+CNV ≪ l} {n m p} {x: X n m} {y: X m p} {Hy: is_surjective y}: !(x⋅y) ≦ !x ⋅ y.
proof: Proof. rewrite leq_cap_neg. rewrite <-negcup, <-dotplsx, cupneg. now rewrite surjective_tx, negtop. Qed.
imports: common lattice monoid kleene normalisation rewriting