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On the chromatic number of simple triangle-free triple systems - MaRDI portal

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On the chromatic number of simple triangle-free triple systems (Q1010856)

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scientific article; zbMATH DE number 6106434
  • Colorings of uniform hypergraphs with large girth
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English
On the chromatic number of simple triangle-free triple systems
scientific article; zbMATH DE number 6106434
  • Colorings of uniform hypergraphs with large girth

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On the chromatic number of simple triangle-free triple systems (English)
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Colorings of uniform hypergraphs with large girth (English)
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7 April 2009
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15 November 2012
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Summary: A hypergraph is simple if every two edges share at most one vertex. It is triangle-free if in addition every three pairwise intersecting edges have a vertex in common. We prove that there is an absolute constant \(c\) such that the chromatic number of a simple triangle-free triple system with maximum degree \(\Delta\) is at most \(c\sqrt{\Delta/\log \Delta}\). This extends a result of Johansson about graphs, and is sharp apart from the constant \(c\).
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hypergraph
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chromatic number
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triangle free triple system
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uniform hypergraph coloring
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