Compositions of Sierpiński–zygmund Functions from the Left
نویسنده
چکیده
A cardinal related to compositions of Sierpiński–Zygmund functions from the left, cleft(SZ), will be considered. We answer a question of K. Ciesielski and T. Natkaniec. In particular, we show that cl(SZ) = (2c)+ if R is not a union of less than c-many meager sets and c is a limit cardinal. If c = ω1, then cl(SZ) is equal to the bounding number of c.
منابع مشابه
Compositions of Sierpiński-zygmund Functions and Related Combinatorial Cardinals
A cardinal related to compositions of Sierpiński-Zygmund functions will be considered. A combinatorial characterization of the cardinal is given and is used to answer some questions of K. Ciesielski and T. Natkaniec. It is shown that the bounding number of the continuum may be strictly smaller than continuum.
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