fact: Fixpoint well_founded_sigT_relation_helper a b (wf_A : Acc RA a) (wf_B : forall a, well_founded (@RB a)) {struct wf_A} : Acc sigT_relation (existT _ a b).
imports: Coq.Setoids.Setoid Coq.Program.Program Coq.Program.Wf Coq.Arith.Wf_nat Coq.Classes.Morphisms Coq.Init.Wf Coq.Lists.SetoidList Coq.Arith.PeanoNat Fiat.Common.Coq__8_4__8_5__Compat