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The discontinuity point sets of quasi-continuous functions

Published online by Cambridge University Press:  17 April 2009

Oleksandr V. Maslyuchenko
Affiliation:
Department of Mathematic, Jurij Fed'kovych Chernivtsi National University, vul Kotsyubyns'kolio 2, Cherniutsi 58012, Ukraine, e-mail: mathan@chnu.cv.ua
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It is proved that a subset E of a hereditarily normal topological space X is a discontinuity point set of some quasi-continuous function f: X → ℝ if and only if E is a countable union of sets En = ĀnBdash aboven where ĀnBn = AnBdash aboven = φ

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 2007

References

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