nhdsNE_of_nhdsNE_sdiff_finite

∀ {X : Type u_3} [inst : TopologicalSpace X] [T1Space X] {x : X} {U s : Set X},
  U ∈ nhdsWithin x {x}ᶜ → Finite ↑s → U \ s ∈ nhdsWithin x {x}ᶜ

In a T1Space, punctured neighborhoods are stable under removing finite sets of points.

Defined in: Mathlib.Topology.DiscreteSubset
Cited by: 3 results in Mathlib
Foundations: Depth 83 from the axioms · uses propext, Classical.choice, Quot.sound
Assumes: TopologicalSpace T1Space

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