proposition: Lemma oppO (F : filter_on T) (f : T -> V) e : - [O_F e of f] =O_F e.
proof: Proof. by rewrite [RHS]bigOE. Qed.
imports: HB(structures) mathcomp(all_ssreflect ssralg ssrnum) mathcomp(mathcomp_extra boolp classical_sets functions) ereal reals signed topology normedtype prodnormedzmodule