fact: Definition ax_HER1_true := ∀ ∀ $1 ≡ $0 → t_f true $1 ≡ t_f true $0.
imports: Lia Arith Undecidability.PCP.PCP Undecidability.PCP.Util.PCP_facts Undecidability.Synthetic.DecidabilityFacts Undecidability(FOL.Utils.FullSyntax) Undecidability(FOL.FSAT) Undecidability.Shared.ListAutomation