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Weight functions on the Kneser graph and the solution of an intersection problem of Sali

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Abstract

LetX, Y be finite sets and suppose thatF is a collection of pairs of sets (F, G),F⊂X,G⊂Y satisfying |F∩F′|≥s, |G∩G′|≥t and |F∩F′|+|G∩G′|≥s+t+1 for all (F, G),F′, G′∈F. Extending a result of Sali, we determine the maximum ofF.

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Authors and Affiliations

  1. C.N.R.S., University of Paris VI, 2 Place Jussieu, 75005, Paris, France

    Peter Frankl

  2. Department of Computer Science, Meiji Univ., 1-1-1 Higashimita, Tama-ku, 214, Kawasaki, Japan

    Norihide Tokushige

Authors
  1. Peter Frankl
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  2. Norihide Tokushige
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Frankl, P., Tokushige, N. Weight functions on the Kneser graph and the solution of an intersection problem of Sali. Combinatorica 13, 413–420 (1993). https://doi.org/10.1007/BF01303513

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