Countable choice and pseudometric spaces
نویسندگان
چکیده
منابع مشابه
On countable choice and sequential spaces
Under the axiom of choice, every first countable space is a FréchetUrysohn space. Although, in its absence even R may fail to be a sequential space. Our goal in this paper is to discuss under which set-theoretic conditions some topological classes, such as the first countable spaces, the metric spaces or the subspaces of R, are classes of Fréchet-Urysohn or sequential spaces. In this context, i...
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ژورنال
عنوان ژورنال: Topology and its Applications
سال: 1998
ISSN: 0166-8641
DOI: 10.1016/s0166-8641(97)00138-7