# Article

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Summary:
We shall show that there is an ultrafilter on singular $\kappa$ with countable cofinality, which cannot be reached from the set of all subuniform ultrafilters by iterating the closure of sets of size $<\kappa$.
References:
[CN] Comfort W.W., Negrepontis S.: The Theory of Ultrafilters. Springer, New York, Heidelberg, Berlin (1974). MR 0396267 | Zbl 0298.02004
[vD] van Douwen E.K.: Remote points. Dissertationes Math. 188 (1981), 1-45. MR 0627526 | Zbl 0525.54018

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