Theorems · Theorem · general topology
isClosed_sUnion
∀ {α : Type u_3} [inst : TopologicalSpace α] [AlexandrovDiscrete α] {S : Set (Set α)},
(∀ s ∈ S, IsClosed s) → IsClosed (⋃₀ S)- Defined in
- Mathlib.Topology.AlexandrovDiscrete
- Cited by
- 2 results in Mathlib
- Foundations
- Depth 64 from the axioms · uses propext, Classical.choice, Quot.sound
Around this declaration
Dashed lines are statement dependencies; solid lines are citations in proofs.
Cites6
Mathlib declarations this one mentions in its statement or cites explicitly in its proof. Plumbing is filtered out.
- Setstatement and proof · cited by 53,352
- TopologicalSpacestatement and proof · cited by 24,529
- IsClosedstatement and proof · cited by 1,639
- Set.sUnionstatement · cited by 392
- AlexandrovDiscretestatement and proof · cited by 45
- alexandrovDiscrete_iff_isClosedproof · cited by 1
Cited by2
Results whose statement or proof uses this declaration.
- isClosed_iUnionproof · cited by 2
- isClopen_sUnionproof · cited by 0