On the cardinality of n-Urysohn and n-Hausdorff spaces.
Autor: | Bonanzinga, Maddalena, Cuzzupé, Maria V., Pansera, Bruno A. |
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Zdroj: | Central European Journal of Mathematics; Feb2014, Vol. 12 Issue 2, p330-336, 7p |
Abstrakt: | Two variations of Arhangelskii’s inequality $$\left| X \right| \leqslant 2^{\chi (X) - L(X)}$$ for Hausdorff X [Arhangel’skii A.V., The power of bicompacta with first axiom of countability, Dokl. Akad. Nauk SSSR, 1969, 187, 967–970 (in Russian)] given in [Stavrova D.N., Separation pseudocharacter and the cardinality of topological spaces, Topology Proc., 2000, 25(Summer), 333–343] are extended to the classes with finite Urysohn number or finite Hausdorff number. [ABSTRACT FROM AUTHOR] |
Databáze: | Complementary Index |
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