Quasi cl-supercontinuous functions and their function spaces

• Autorzy: Kohli J. K. , Aggarwal J.
• Języki publikacji: EN

Abstrakty

EN

A new class of functions called 'quasi cl-supercontinuous functions' is introduced. Basic properties of quasi cl-supercontinuous functions are studied and their place in the hierarchy of variants of continuity that already exist in the mathematical literature is elaborated. The notion of quasi cl-supercontinuity, in general, is independent of continuity but coincides with cl-supercontinuity (clopen continuity) (Applied General Topology 8(2) (2007), 293-300; Indian J. Pure Appl. Math. 14(6) (1983), 767-772), a significantly strong form of continuity, if range is a regular space. The class of quasi cl-supercontinuous functions properly contains each of the classes of (i) quasi perfectly continuous functions and (ii) almost cl-supercontinuous functions; and is strictly contained in the class of quasi z-supercontinuous functions. Moreover, it is shown that if X is sum connected (e.g. connected or locally connected) and Y is Hausdorff, then the function space Lq(X, Y ) of all quasi cl-supercontinuous functions as well as the function space Lq(X, Y ) of all almost cl-supercontinuous functions from X to Y is closed in Y X in the topology of pointwise convergence.

Słowa kluczowe

EN

almost cl-supercontinuous function; almost perfectly continuous function; quasi hyperconnected space; quasi zero dimensional space; sum connected space; topology of pointwise convergence

• Wydawca: De Gruyter
• Czasopismo: Demonstratio Mathematica
• Rocznik: 2012
• Tom: Vol. 45, nr 3
• Strony: 677--697
• Opis fizyczny: Bibliogr. 51 poz., rys.

Twórcy

autor

Kohli J. K.

autor

Aggarwal J.

• Department Of Mathematics Hindu College University Of Delhi Delhi 110007, India,

Bibliografia

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