Section Arg2.
Variable gf : rel2 T0 T1 -> rel2 T0 T1.
Arguments gf : clear implicits.

Theorem paco2_acc: forall
l r (OBG: forall rr (INC: r <2= rr) (CIH: l <2= rr), l <2= paco2 gf rr),
l <2= paco2 gf r.