\forall (c2: C).(\forall (c3: C).(\forall (h: nat).(\forall (d: nat).((drop
h d c2 c3) \to (\forall (hds: PList).(\forall (c1: C).((drop1 hds c1 c2) \to
(drop1 (PConsTail hds h d) c1 c3))))))))
\forall (c2: C).(\forall (c3: C).(\forall (h: nat).(\forall (d: nat).((drop
h d c2 c3) \to (\forall (hds: PList).(\forall (c1: C).((drop1 hds c1 c2) \to
(drop1 (PConsTail hds h d) c1 c3))))))))