Metadata aliases: [] shorthands: {} created: 2022-01-30 22:12:29 modified: 2022-01-30 22:16:04 Let be a topological space and its topology. A topology is first countable if for each , there is a countable collection of neighborhoods of such that for any neighborhood of , there is an so .
aliases: [] shorthands: {} created: 2022-01-30 22:12:29 modified: 2022-01-30 22:16:04