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


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

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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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