Geodesic
Erdös-Ko-Rado from intersecting shadows
Discussiones Mathematicae. Graph Theory, Tome 32 (2012) no. 2, pp. 379-382.

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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 
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Katona, Gyula; Kisvölcsey, Ákos. Erdös-Ko-Rado from intersecting shadows. Discussiones Mathematicae. Graph Theory, Tome 32 (2012) no. 2, pp. 379-382. http://geodesic.mathdoc.fr/item/DMGT_2012_32_2_a15/

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