The character of 𝜔₁ in first countable spaces

Fleissner, William G.

doi:10.1090/S0002-9939-1977-0438272-7

The character of $\omega _{1}$ in first countable spaces
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Proc. Amer. Math. Soc. 62 (1977), 149-155 Request permission

Abstract:

We define a cardinal function $\chi (P,Q)$, where P and Q are properties of topological spaces. We show that it is consistent and independent that $\chi ({\omega _1},\;{\text {first}}\;{\text {countable}}) = {\omega _1}$.

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