fact: Hypothesis HF2 : forall b1 b2 x y, i_f b1 x =/= i_dum -> i_f b1 x == i_f b2 y -> x == y /\ b1 = b2.
imports: Lia Arith Undecidability.PCP.PCP Undecidability.PCP.Util.PCP_facts Undecidability.Synthetic.DecidabilityFacts Undecidability(FOL.Utils.FullSyntax) Undecidability(FOL.FSAT) Undecidability.Shared.ListAutomation