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On the chromatic number of set systems - MaRDI portal

On the chromatic number of set systems (Q2748418)

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scientific article; zbMATH DE number 1659408
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On the chromatic number of set systems
scientific article; zbMATH DE number 1659408

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    On the chromatic number of set systems (English)
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    10 February 2002
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    extremal set theory
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    uniform hypergraphs
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    property B
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    An \((r,l)\) system is an \(r\)-uniform hypergraph in which every set of \(l\) vertices lies in at most one edge. The problem is: what is the minimum number of edges in an \((r,l)\)-system that is not \(k\)-colourable. This question in the case of \(l=2\) is due to Paul Erdős and L. Lovász. This paper gives an essentially identical lower and upper bound (up to constants) for this minimum. The proofs are probabilistic.
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