fact: Definition Formula_depth_rec_rec : forall P : Formula -> Set, (forall a : Formula, (forall b : Formula, lt_depth b a -> P b) -> P a) -> forall (n : nat) (b : Formula), depth b <= n -> P b.
imports: Coq(Lists.List Ensembles Peano_dec Eqdep_dec Arith Compare_dec Utf8) hydras(Ackermann.misc Compat815 )