proposition: Fact nat2Zp_invertible n : Zp_invertible 〚n〛 <-> is_gcd p n 1.
proof: Proof. rewrite Zp_invertible_spec. symmetry; apply is_gcd_rem. Qed.
imports: Arith Lia ZArith List Permutation Eqdep_dec Undecidability.Shared.Libs.DLW.Utils(utils_tac utils_list gcd prime binomial sums php) Undecidability.H10.ArithLibs(matrix)