Abstract
Let p be a prime, and let L be a set of s congruence classes modulo p. Let \({\mathcal{H}}\) be a family of subsets of [n] such that the size modulo p of each member of \({\mathcal{H}}\) is not in L, but the size modulo p of every intersection of k distinct members of \({\mathcal{H}}\) is in L. We prove that \(|{{\mathcal{H}}}|\le(k-1)\sum_{i=0}^s {n-1\choose i}\) , improving the bound due to Grolmusz and generalizing results proved for k = 2 by Snevily.
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Work supported in part by the NSA under Award No. MDA904-03-1-0037.
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Cao, W., Hwang, KW. & West, D.B. Improved Bounds on Families Under k-wise Set-Intersection Constraints. Graphs and Combinatorics 23, 381–386 (2007). https://doi.org/10.1007/s00373-007-0741-0
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DOI: https://doi.org/10.1007/s00373-007-0741-0