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Comparing almost-disjoint families - MaRDI portal

Comparing almost-disjoint families (Q1087541)

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scientific article; zbMATH DE number 3987278
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Comparing almost-disjoint families
scientific article; zbMATH DE number 3987278

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    Comparing almost-disjoint families (English)
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    1986
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    If \(\{A_{\alpha}:\alpha <\kappa \}\), \(\{B_{\alpha}:\alpha <\kappa \}\) are almost-disjoint families of countable sets, \(| A_{\alpha}\cap A_{\beta}| \leq | B_{\alpha}\cap B_{\beta}|\) for \(\alpha <\beta <\kappa\), and there are finite subsets \(f(B_{\alpha})\subseteq B_{\alpha}\) such that the system \(\{B_{\alpha}-f(B_{\alpha}):\alpha <\kappa \}\) is disjoint, then the same is true for \(\{A_{\alpha}:\alpha <\kappa \}\). This implies that this property holds if \(| A_{\alpha}\cap A_{\beta}| \leq n\) for a fixed natural number n, a strengthening of Miller's theorem.
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    almost-disjoint sets
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    Miller's theorem
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