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GENERALIZED FRÉCHET-URYSOHN SPACES
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 Title & Authors
GENERALIZED FRÉCHET-URYSOHN SPACES
Hong, Woo-Chorl;
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 Abstract
In this paper, we introduce some new properties of a topological space which are respectively generalizations of -Urysohn property. We show that countably AP property is a sufficient condition for a space being countable tightness, sequential, weakly first countable and symmetrizable, to be ACP, , first countable and semimetrizable, respectively. We also prove that countable compactness is a sufficient condition for a countably AP space to be countably . We then show that a countably compact space satisfying one of the properties mentioned here is sequentially compact. And we show that a countably compact and countably AP space is maximal countably compact if and only if it is . We finally obtain a sufficient condition for the ACP closure operator to be a Kuratowski topological closure operator and related results.
 Keywords
;sequential;countably ;countable tightness;AP;countably AP;WAP;ACP;WACP;countably compact;
 Language
English
 Cited by
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2.
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대한수학회논문집, 2010. vol.25. 3, pp.477-484 crossref(new window)
4.
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5.
ON SPACES WHICH HAVE COUNTABLE TIGHTNESS AND RELATED SPACES,;

호남수학학술지, 2012. vol.34. 2, pp.199-208 crossref(new window)
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호남수학학술지, 2013. vol.35. 3, pp.541-550 crossref(new window)
7.
A GENERALIZATION OF A SEQUENTIAL SPACE AND RELATED SPACES,;;

호남수학학술지, 2014. vol.36. 2, pp.425-434 crossref(new window)
1.
SOME NECESSARY AND SUFFICIENT CONDITIONS FOR A FRÉCHET-URYSOHN SPACE TO BE SEQUENTIALLY COMPACT, Communications of the Korean Mathematical Society, 2009, 24, 1, 145  crossref(new windwow)
2.
A NOTE ON SPACES DETERMINED BY CLOSURE-LIKE OPERATORS, East Asian mathematical journal, 2016, 32, 3, 365  crossref(new windwow)
3.
A NOTE ON THE FIRST LAYERS OF ℤp-EXTENSIONS, Communications of the Korean Mathematical Society, 2009, 24, 1, 1  crossref(new windwow)
4.
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5.
NEW CARDINAL FUNCTIONS RELATED TO ALMOST CLOSED SETS, Honam Mathematical Journal, 2013, 35, 3, 541  crossref(new windwow)
6.
A NOTE ON SPACES WHICH HAVE COUNTABLE TIGHTNESS, Communications of the Korean Mathematical Society, 2011, 26, 2, 297  crossref(new windwow)
7.
A GENERALIZATION OF A SEQUENTIAL SPACE AND RELATED SPACES, Honam Mathematical Journal, 2014, 36, 2, 425  crossref(new windwow)
8.
Diagonal sequence property in Banach spaces with weaker topologies, Journal of Mathematical Analysis and Applications, 2009, 350, 2, 838  crossref(new windwow)
9.
ON SPACES WHICH HAVE COUNTABLE TIGHTNESS AND RELATED SPACES, Honam Mathematical Journal, 2012, 34, 2, 199  crossref(new windwow)
10.
ON SPACES IN WHICH THE THREE MAIN KINDS OF COMPACTNESS ARE EQUIVALENT, Communications of the Korean Mathematical Society, 2010, 25, 3, 477  crossref(new windwow)
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