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Equivalence of the Rothberger, \(k\)-Rothberger, and restricted Menger games - MaRDI portal

Equivalence of the Rothberger, \(k\)-Rothberger, and restricted Menger games (Q1738935)

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Equivalence of the Rothberger, \(k\)-Rothberger, and restricted Menger games
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    Equivalence of the Rothberger, \(k\)-Rothberger, and restricted Menger games (English)
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    24 April 2019
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    The restricted Menger game on a topological space $X$ requires the second player to specify a positive integer $k_0$ and thereafter at the $n^{\text{th}}$ round the first player chooses an open cover $\mathcal U_n$ of $X$ then the second player chooses $\mathcal V_n\subset\mathcal U_n$ with $|\mathcal V_n|=k_n$ and positive integer $k_{n+1}$; the second player wins iff $X=\cup_{n=0}^\infty\cup\mathcal V_n$. The main result shows that the restricted Menger game and the Rothberger game (where $k_n=1$ for all $n$) are equivalent on a Hausdorff space.
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    covering games
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    Rothberger game
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    Menger game
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