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arXiv · 0911.0563

Judicious partitions of 3-uniform hypergraphs

John Haslegrave
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Abstract

The vertices of any graph with $m$ edges can be partitioned into two parts so that each part meets at least $\frac{2m}{3}$ edges. Bollobás and Thomason conjectured that the vertices of any $r$-uniform graph may be likewise partitioned into $r$ classes such that each part meets at least $cm$ edges, with $c=\frac{r}{2r-1}$. In this paper, we prove this conjecture for the case $r=3$. In the course of the proof we shall also prove an extension of the graph case which was conjectured by Bollobás and Scott.

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John Haslegrave. 2009-11-03. Judicious partitions of 3-uniform hypergraphs. https://doi.org/10.1007/s00493-012-2696-x

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