Section Arg4.
Variable gf : rel4 T0 T1 T2 T3 -> rel4 T0 T1 T2 T3.
Arguments gf : clear implicits.

Theorem paco4_acc: forall
l r (OBG: forall rr (INC: r <4= rr) (CIH: l <4= rr), l <4= paco4 gf rr),
l <4= paco4 gf r.