A note on kernels and Sperner's Lemma

نویسندگان

  • Tamás Király
  • Júlia Pap
چکیده

The kernel-solvability of perfect graphs was first proved by Boros and Gurvich, and later Aharoni andHolzmangave a shorter proof. Bothproofswere based on Scarf’s Lemma. In this note we show that a very simple proof can be given using a polyhedral version of Sperner’s Lemma. In addition, we extend the Boros–Gurvich theorem to h-perfect graphs and to a more general setting. © 2009 Elsevier B.V. All rights reserved.

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عنوان ژورنال:
  • Discrete Applied Mathematics

دوره 157  شماره 

صفحات  -

تاریخ انتشار 2009