Sparse hypergraphs with low independence number

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Sparse hypergraphs with low independence number

Let K (3) 4 denote the complete 3-uniform hypergraph on 4 vertices. Ajtai, Erdős, Komlós, and Szemerédi (1981) asked if there is a function ω(d) → ∞ such that every 3-uniform, K (3) 4 -free hypergraph H with N vertices and average degree d has independence number at least N d1/2 ω(d). We answer this question by constructing a 3-uniform, K (3) 4 -free hypergraph with independence number at most ...

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ژورنال

عنوان ژورنال: Combinatorica

سال: 2015

ISSN: 0209-9683,1439-6912

DOI: 10.1007/s00493-014-3219-8