General topology

Point-finite collection

In mathematics, a collection   of subsets of a topological space is said to be point-finite if every point of lies in only finitely many members of . A topological space in which every open cover admits a point-finite open refinement is called metacompact. Every locally finite collection of subsets of a topological space is also point-finite. A topological space in which every open cover admits a locally finite open refinement is called paracompact. Every paracompact space is therefore metacompact. (Wikipedia).

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Related pages

Metacompact space | Topological space | Locally finite collection | Mathematics | Paracompact space | Refinement (topology)