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作者单位:Miroslav Repicky (1)
1. Mathematical Institute, Slovak Academy of Sciences, Gre?ákova 6, 040 01, Kosice, Slovak Republic
刊物类别:Mathematics and Statistics
刊物主题:Mathematics Mathematical Logic and Foundations Mathematics Algebra
出版者:Springer Berlin / Heidelberg
ISSN:1432-0665
文摘
We study the sets of symmetric continuity of real functions in connection with the sets of continuity. We prove that sets of reals of cardinality \({ < \mathfrak{p}}\) and subsets of weakly independent \({G_\delta}\) sets of reals are sets of symmetric continuity. The latter strengthens a similar result of Darji. We improve results of Fried and Belna saying that the set of points of symmetric continuity of a real function that are not continuity points does not contain a nonmeager set with Baire property and has inner measure zero by introducing another notion of smallness below meager and measure zero. Keywords Real function Sets of symmetric continuity Weakly independent set Measure zero Meager