Weight: Difference between revisions

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==Particular cases==
==Particular cases==


If the weight is countable, we call it a [[second-countable space]].
If the weight is finite or countable, we call the space a [[second-countable space]].

Latest revision as of 04:20, 27 January 2012

Template:Topospace cardinal function

Definition

The weight of a topological space is the minimum possible cardinality of a basis for the topological space (if finite, we take the weight as countable).

Particular cases

If the weight is finite or countable, we call the space a second-countable space.