Note Erdős–Ko–Rado from intersecting shadows

نویسندگان

  • Gyula O. H. Katona
  • Ákos Kisvölcsey
چکیده

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.

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تاریخ انتشار 2011