import OAI.Combinatorics.InfiniteMatroid.CoveringReduction import OAI.Combinatorics.InfiniteMatroid.PairDuality import OAI.Combinatorics.InfiniteMatroid.Main namespace OAI namespace InfiniteMatroidCounterexample open Set Matroid theorem separate_covering_packing_counterexamples : (∃ (F : Set E) (M : Bool → Matroid E), (∀ i, (M i).E = F) ∧ ¬ CoveringConjectureFor F M) ∧ (∃ (F : Set E) (M : Bool → Matroid E), (∀ i, (M i).E = F) ∧ ¬ PackingConjectureFor F M) := by obtain ⟨_, _, M₀, M₁, hE₀, hE₁, _, _, _, hno⟩ := main let M : Bool → Matroid E := fun i ↦ if i then M₁ else M₀ have hg : ∀ i, (M i).E = univ := by intro i cases i <;> simp [M, hE₀, hE₁] have hn : ¬ HasPackingCovering (M false) (M true) := hno obtain ⟨C, N, hN, hnc, hcond⟩ := separate_covering_of_no_packingCovering hg hn refine ⟨⟨C, N, hN, fun h ↦ hnc (h.mpr hcond)⟩, ⟨C, fun i ↦ (N i).dual, ?_, ?_⟩⟩ · simpa only [Matroid.dual_ground] using hN · exact separate_packing_of_covering_counterexample hN hnc hcond end InfiniteMatroidCounterexample end OAI