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arXiv · 1405.0065

Perfect Packings in Quasirandom Hypergraphs II

John Lenz·Dhruv Mubayi
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Abstract

For each of the notions of hypergraph quasirandomness that have been studied, we identify a large class of hypergraphs F so that every quasirandom hypergraph H admits a perfect F-packing. An informal statement of a special case of our general result for 3-uniform hypergraphs is as follows. Fix an integer r >= 4 and 0<p<1. Suppose that H is an n-vertex triple system with r|n and the following two properties: * for every graph G with V(G)=V(H), at least p proportion of the triangles in G are also edges of H, * for every vertex x of H, the link graph of x is a quasirandom graph with density at least p. Then H has a perfect $K_r^{(3)}$-packing. Moreover, we show that neither hypotheses above can be weakened, so in this sense our result is tight. A similar conclusion for this special case can be proved by Keevash's hypergraph blowup lemma, with a slightly stronger hypothesis on H.

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John Lenz, Dhruv Mubayi. 2014-05-01. Perfect Packings in Quasirandom Hypergraphs II. https://doi.org/10.1017/s0963548315000267

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