Notation "#<< l , x >>#" := (mcontra _ l x).Notation liftk := (Kn.lift p).

(* Specifications: *)
Lemma cbl_cons n (a: vect n) l k x : cbl n l k x -> cbl n (a::l) k x.
Lemma cbl_joinl n (l: list (vect n)) : l <> nil -> (forall x, In x l -> hom n 1 x) -> cbl n l (pred (length l)) (joinl n l).
Lemma decomp_one_factor_hom n (l: list (vect n)) M : l <> nil -> decomposable n l M -> hom n 1 (one_factor n (pred (length l)) M).
Lemma decomp_one_factor0 n (l: list (vect n)) M : decomposable n l M -> one_factor n (pred (length l)) M = 0 -> M = 0.