Mathlib Map

Structures · Topology

SigmaCompactSpace

A σ-compact space is a space that is the union of a countable collection of compact subspaces. Note that a locally compact separable T₂ space need not be σ-compact. The sequence can be extracted using compactCovering.

Defined in
Mathlib.Topology.Compactness.SigmaCompact
Shape
One type argument · adds isSigmaCompact_univ

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Concrete types that are instances4

  • Prod
  • ULift
  • Sum
  • Sigma

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Assumed by72

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