theorem drop_skip_bind:
\forall (h: nat).(\forall (d: nat).(\forall (c: C).(\forall (e: C).((drop h
d c e) \to (\forall (b: B).(\forall (u: T).(drop h (S d) (CHead c (Bind b)
theorem drop_skip_bind:
\forall (h: nat).(\forall (d: nat).(\forall (c: C).(\forall (e: C).((drop h
d c e) \to (\forall (b: B).(\forall (u: T).(drop h (S d) (CHead c (Bind b)