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Apr 12, 2018 at 21:42 comment added Douglas Somerset This is the Arhnangelskii-Franklin paper projecteuclid.org/euclid.mmj/1029000034
Apr 12, 2018 at 18:15 comment added YCor Ah, I didn't think of the quotient, but indeed it can't be Hausdorff because it's (quasi-)compact, countable, with no isolated point. I don't know the Arhangelskii-Franklin example. I didn't even know that there could be countable spaces that are not first-countable; I haven't thought about this one.
Apr 12, 2018 at 17:26 comment added Douglas Somerset The quotient space would seem to have every point a limit point and to be nowhere first countable. Is this the same as the Arhangelskii-Franklin example (which came to mind after I had posed the question)?
Apr 12, 2018 at 17:06 vote accept Douglas Somerset
Apr 12, 2018 at 16:48 comment added YCor Yep, homeomorphic copies of this space and partition appear in zillions of ways.
Apr 12, 2018 at 16:46 comment added Nate Eldredge Equivalently, this is the ordinal $\omega^2$ with the order topology. It contains countably many limit ordinals and countably many successors, so you can partition it into sets $F_n$ containing one of each. The compactification is $\omega^2+1$.
Apr 12, 2018 at 15:08 history answered YCor CC BY-SA 3.0