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 β E) {U K : Set π}
(hK : IsCompact K) (hKU : K β U) :
(K β© (MeromorphicOn.divisor f U).support).FiniteComplete declaration
Lean source
Full Lean sourceLean 4
lemma divisor_support_inter_compact_finite (f : π β E) {U K : Set π} (hK : IsCompact K) (hKU : K β U) : (K β© (MeromorphicOn.divisor f U).support).Finite := by classical set D : Function.locallyFinsuppWithin U β€ := MeromorphicOn.divisor f U have hloc : β x β K, β V : Set π, V β π x β§ Set.Finite (V β© D.support) := by intro x hxK rcases D.supportLocallyFiniteWithinDomain x (hKU hxK) with β¨V, hV, hfinβ© exact β¨V, hV, hfinβ© 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 β¨t, htβ© have hsub : K β© D.support β β x β t, (V (x : π) x.2 β© D.support) := by intro y hy rcases hy with β¨hyK, hySβ© have hycov : y β β x β t, V (x : π) x.2 := ht hyK rcases Set.mem_iUnion.1 hycov with β¨x, hycov'β© rcases Set.mem_iUnion.1 hycov' with β¨hxT, hyVβ© refine Set.mem_iUnion.2 β¨x, Set.mem_iUnion.2 ?_β© exact β¨hxT, β¨hyV, hySβ©β© have hfinU : Set.Finite (β x β t, (V (x : π) x.2 β© D.support)) := by classical refine (t.finite_toSet).biUnion ?_ intro x hx simpa using (hVfin (x : π) x.2) exact hfinU.subset hsub