I see similar results on this site, but I am unable to find the explicit base, $$\{B(x,1/n):x\in \mathbb{C}, x=a+ib,a,b\in \mathbb{Q},n\in \mathbb{N}\}\cup \{0\}^c$$.
Will this work?
2026-03-25 07:41:15.1774424475
Countable base for the one point compactification topology on $\mathbb{C}$
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