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arXiv · 1206.6554

On the cardinality of the $θ$-closed hull of sets II

Filippo Cammaroto·Andrei Catalioto·Bruno Antonio Pansera·Jack Porter
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Abstract

The research in this paper is a continuation of the investigation of the cardinality of the $θ$-closed hull of subsets of spaces. This research obtains new upper bounds of the cardinality of the $θ$-closed hull of subsets using cardinal functions of $θ$-bitightness (\cite{Ca-Ko}), finite $θ$-bitightness (\cite{Ca-Ca-Pa-Ts}) and $θ$-bitightness small number (\cite{Ca-Ca-Pa-Ts}) of spaces. In the final section, examples of spaces are presented including one that answers a question posed in \cite{Bo-Ca-Ma} and \cite{Bo-Pa}.

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Filippo Cammaroto, Andrei Catalioto, Bruno Antonio Pansera, Jack Porter. 2012-12-17. On the cardinality of the $θ$-closed hull of sets II. https://arxiv.org/abs/1206.6554

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