fact: Definition tree_induction (T:Tree) (x:T) (P:T->Type) (p0 : P x) (pn : ∏ z (ne:x != z), P (step T ne) -> P z) : ∏ z, P z.
imports: UniMath.Foundations.All UniMath.MoreFoundations.Nat UniMath.MoreFoundations.Notations