A conjecture of V. So s [3] is proved that any set of 3 4 ( n 3 )+cn 2 triples from an n-set, where c is a suitable absolute constant, must contain a copy of the Fano configuration (the projective plane of order two). This is an asymptotically sharp estimate.
On the Degree, Size, and Chromatic Index of a Uniform Hypergraph
β Scribed by Noga Alon; Jeong Han Kim
- Publisher
- Elsevier Science
- Year
- 1997
- Tongue
- English
- Weight
- 274 KB
- Volume
- 77
- Category
- Article
- ISSN
- 0097-3165
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β¦ Synopsis
Let H be a k-uniform hypergraph in which no two edges share more than t common vertices, and let D denote the maximum degree of a vertex of H. We conjecture that for every =>0, if D is sufficiently large as a function of t, k, and =, then the chromatic index of H is at most (t&1+1Γt+=) D. We prove this conjecture for the special case of intersecting hypergraphs in the following stronger form: If H is an intersecting k-uniform hypergraph in which no two edges share more than t common vertices and D is the maximum degree of a vertex of H, where D is sufficiently large as a function of k, then H has at most (t&1+1Γt) D edges.
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