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Transcript
second countable∗
rspuzio†
2013-03-21 13:01:34
A topological space is said to be second countable if it has a countable basis.
It can be shown that a second countable space is both Lindelöf and separable,
although the converses fail. For instance, the lower limit topology on the real
line is both Lindelöf and separable, but not second countable.
∗ hSecondCountablei created: h2013-03-21i by: hrspuzioi version: h31162i Privacy setting:
h1i hDefinitioni h54D70i
† This text is available under the Creative Commons Attribution/Share-Alike License 3.0.
You can reuse this document or portions thereof only if you do so under terms that are
compatible with the CC-BY-SA license.
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