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arXiv · 1511.00563

Hedgehogs are not colour blind

David Conlon·Jacob Fox·Vojtěch Rödl
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Abstract

We exhibit a family of $3$-uniform hypergraphs with the property that their $2$-colour Ramsey numbers grow polynomially in the number of vertices, while their $4$-colour Ramsey numbers grow exponentially. This is the first example of a class of hypergraphs whose Ramsey numbers show a strong dependence on the number of colours.

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David Conlon, Jacob Fox, Vojtěch Rödl. 2015-11-02. Hedgehogs are not colour blind. https://arxiv.org/abs/1511.00563

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