ZFC existence of a countable Fréchet–Urysohn space with π-weight equal to 𝔟
Determine, within ZFC, whether there exists a countable Fréchet–Urysohn topological space whose π-weight is exactly the bounding number 𝔟.
References
Corollary \ref{cor} is included because it is not known if, in ZFC, there is a countable Fr echet-Urysohn space with $\pi$-weight exactly $\mathfrak b$.
— New examples in the study of selectively separable spaces
(2509.22590 - Dow et al., 26 Sep 2025) in Introduction, paragraph following Corollary \ref{cor}