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Contra-continuous functions and strongly S-closed spaces

DOI: 10.1155/s0161171296000427

Keywords: strongly S-closed , closed cover , contra-continuous , LC-continuous , perfectly continuous , strongly continuous , FCC.

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Abstract:

In 1989 Ganster and Reilly [6] introduced and studied the notion of LC-continuous functions via the concept of locally closed sets. In this paper we consider a stronger form of LC-continuity called contra-continuity. We call a function f:(X, ) ¢ ’(Y, ) contra-continuous if the preimage of every open set is closed. A space (X, ) is called strongly S-closed if it has a finite dense subset or equivalently if every cover of (X, ) by closed sets has a finite subcover. We prove that contra-continuous images of strongly S-closed spaces are compact as well as that contra-continuous, 2-continuous images of S-closed spaces are also compact. We show that every strongly S-closed space satisfies FCC and hence is nearly compact.

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