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Tiling 3-uniform hypergraphs with K_4^3-2e

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 Added by Louis DeBiasio
 Publication date 2011
  fields
and research's language is English




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Let K_4^3-2e denote the hypergraph consisting of two triples on four points. For an integer n, let t(n, K_4^3-2e) denote the smallest integer d so that every 3-uniform hypergraph G of order n with minimum pair-degree delta_2(G) geq d contains floor{n/4} vertex-disjoint copies of K_4^3-2e. Kuhn and Osthus proved that t(n, K_4^3-2e) = (1 + o(1))n/4 holds for large integers n. Here, we prove the exact counterpart, that for all sufficiently large integers n divisible by 4, t(n, K_4^3-2e) = n/4 when n/4 is odd, and t(n, K_4^3-2e) = n/4+1 when n/4 is even. A main ingredient in our proof is the recent `absorption technique of Rodl, Rucinski and Szemeredi.



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