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arXiv · 1308.0611

The 1-2-3 Conjecture for Hypergraphs

Maciej Kalkowski·Michał Karoński·Florian Pfender
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Abstract

A weighting of the edges of a hypergraph is called vertex-coloring if the weighted degrees of the vertices yield a proper coloring of the graph, i.e., every edge contains at least two vertices with different weighted degrees. In this paper we show that such a weighting is possible from the weight set {1,2,...,r+1} for all hypergraphs with maximum edge size r>3 and not containing edges solely consisting of identical vertices. The number r+1 is best possible for this statement. Further, the weight set {1,2,3,4,5} is sufficient for all hypergraphs with maximum edge size 3, up to some trivial exceptions.

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Maciej Kalkowski, Michał Karoński, Florian Pfender. 2013-08-02. The 1-2-3 Conjecture for Hypergraphs. https://arxiv.org/abs/1308.0611

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