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ArticleOriginal scientific text

Title

Erdös-Ko-Rado from intersecting shadows

Authors 1, 1

Affiliations

  1. 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

ENG
Kneser graph, coclique, intersecting family, shadow

Bibliography

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Discussiones Mathematicae Graph Theory
2012/32/2
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Pages:
379-382
Main language of publication
English
Received
2011-04-28
Accepted
2011-08-06
Published
2012

DOI: 10.7151/dmgt.1620

Exact and natural sciences