# ON SPACES WHICH HAVE COUNTABLE TIGHTNESS AND RELATED SPACES

• Hong, Woo-Chorl (Department of Mathematics Education, Pusan National University)
• Accepted : 2012.03.19
• Published : 2012.06.25

#### Abstract

In this paper, we study some properties of spaces having countable tightness and spaces having weakly countable tightness. We obtain some necessary and sufficient conditions for a space to have countable tightness. And we introduce a new concept of weakly countable tightness which is a generalization of countable tightness and show some properties of spaces having weakly countable tightness.

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2. A NOTE ON SPACES DETERMINED BY CLOSURE-LIKE OPERATORS vol.32, pp.3, 2016, https://doi.org/10.7858/eamj.2016.027