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A topological space with a countable base.
wp-second-countablenlab-second-countable-spacetopology-without-tearsEach relation below ends at this concept.
This is an authored directed relation from the source endpoint to the target endpoint.
Require a countable basis for the topology.
Keep the existing data and select the subclass satisfying an additional law, existence condition, finiteness condition, or other property.
wp-second-countabletopology-without-tearsEach relation below starts at this concept.
This is an authored directed relation from the source endpoint to the target endpoint.
Restricting a countable global base to neighborhoods of a point gives a countable local base.
Record a genuine theorem implication that is not part of the target definition; these edges may point toward a weaker structure.
wp-second-countablewp-first-countabletopology-without-tearsThis is an authored directed relation from the source endpoint to the target endpoint.
Supply second countability.
Feed several structures into a construction junction and impose compatibility between them.
wp-manifoldtopology-without-tears