Does separability and/or second countability implies $T_2$ or higher axiom sets?
My intuition is "no". Even $T_0$ space can be separability and/or second countability?
2026-03-25 03:18:04.1774408684
Similarity and Difference between Separable Space and Separated space?
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No. Consider $X = \{a,b\}$ just two elements and $\mathcal{T} = \{\emptyset, X\}$. This is separable, second countable, and not even $T_0$.