fact: Fixpoint istrunc_allnullhomot {n : trunc_index} {X : Type} (HX : forall (f : Sphere n.+2 -> X), NullHomotopy f) {struct n} : IsTrunc n.+1 X.
imports: Basics Types WildCat.Equiv NullHomotopy Homotopy.Suspension Pointed Truncations Spaces.Circle Spaces.TwoSphere