On the chromatic number of Kneser hypergraphs

Matoušek, Jiří

doi:10.1090/S0002-9939-02-06371-2

On the chromatic number of Kneser hypergraphs
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Proc. Amer. Math. Soc. 130 (2002), 2509-2514 Request permission

Abstract:

We give a simple and elementary proof of Kříž’s lower bound on the chromatic number of the Kneser $r$-hypergraph of a set system $\mathcal {S}$.

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