Gyula O.H. Katona and Ákos Kisvölcsey Alfréd Rényi Institute of Mathematics, Hungarian Academy of Sciences 1053 Budapest, Reáltanoda u. 13--15, Hungary

## Abstract

A set system is called t-intersecting if every two members meet each other in at least t elements. Katona determined the minimum ratio of the shadow and the size of such families and showed that the Erdős-Ko-Rado theorem immediately follows from this result. The aim of this note is to reproduce the proof to obtain a slight improvement in the Kneser graph. We also give a brief overview of corresponding results.

Keywords: Kneser graph, coclique, intersecting family, shadow

2010 Mathematics Subject Classification: 05C35, 05D05.

## References

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