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AlexKontorovich/PrimeNumberTheoremAnd
Source indexedlemma Β· leanprover/lean4:v4.32.0

MeromorphicOn.divisor_support_inter_compact_finite

PrimeNumberTheoremAnd.Mathlib.Analysis.Meromorphic.DivisorSupport Β· PrimeNumberTheoremAnd/Mathlib/Analysis/Meromorphic/DivisorSupport.lean:64 to 91

Mathematical statement

Exact Lean statement

lemma divisor_support_inter_compact_finite (f : π•œ β†’ E) {U K : Set π•œ}
    (hK : IsCompact K) (hKU : K βŠ† U) :
    (K ∩ (MeromorphicOn.divisor f U).support).Finite

Complete declaration

Lean source

Canonical source
Full Lean sourceLean 4
lemma divisor_support_inter_compact_finite (f : π•œ β†’ E) {U K : Set π•œ}    (hK : IsCompact K) (hKU : K βŠ† U) :    (K ∩ (MeromorphicOn.divisor f U).support).Finite := by  classical  set D : Function.locallyFinsuppWithin U β„€ := MeromorphicOn.divisor f U  have hloc :      βˆ€ x ∈ K, βˆƒ V : Set π•œ, V ∈ 𝓝 x ∧ Set.Finite (V ∩ D.support) := by    intro x hxK    rcases D.supportLocallyFiniteWithinDomain x (hKU hxK) with ⟨V, hV, hfin⟩    exact ⟨V, hV, hfin⟩  choose V hVnhds hVfin using hloc  rcases hK.elim_nhds_subcover' (U := fun x hx => V x hx) (hU := fun x hx => hVnhds x hx) with    ⟨t, ht⟩  have hsub :      K ∩ D.support βŠ† ⋃ x ∈ t, (V (x : π•œ) x.2 ∩ D.support) := by    intro y hy    rcases hy with ⟨hyK, hyS⟩    have hycov : y ∈ ⋃ x ∈ t, V (x : π•œ) x.2 := ht hyK    rcases Set.mem_iUnion.1 hycov with ⟨x, hycov'⟩    rcases Set.mem_iUnion.1 hycov' with ⟨hxT, hyV⟩    refine Set.mem_iUnion.2 ⟨x, Set.mem_iUnion.2 ?_⟩    exact ⟨hxT, ⟨hyV, hyS⟩⟩  have hfinU : Set.Finite (⋃ x ∈ t, (V (x : π•œ) x.2 ∩ D.support)) := by    classical    refine (t.finite_toSet).biUnion ?_    intro x hx    simpa using (hVfin (x : π•œ) x.2)  exact hfinU.subset hsub