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Fixes typo in the title
Luc Guyot
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A criterion for second countability!

Let $(X,\tau)$ be a topological space.

Assume for any arbitrary topological base $\mathcal{E}$ of $\tau$ we have that: the Borel sigma algebras coming form $\mathcal{E}$ and $\tau$ are the same. Can we conclude that $X$ is second countable ?!

ABB
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