Quasi Cl-Supercontinuous Functions and Their Function Spaces

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 L-q(X,Y) of all quasi cl-supercontinuous functions as well as the function space L-delta(X,Y) of all almost cl-supercontinuous functions from X to Y is closed in Y X in the topology of pointwise convergence.