Quasicontinuous functions with a little symmetry are extendable and related combinatorial cardinals

by

Francis Jordan

Real Anal. Exchange 25(1) (1999-2000), 485-488.

It is shown that if a function f:R-->R is quasicontinuous and has a graph which is bilaterally dense in itself, then f must be extendable to a connectivity function F:R2-->R and the set of discontinuity points of f is f-negligible. This improves a result of H. Rosen. A similar result for symmetrically continuous functions follows immediately.

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Last modified December 6, 2000.