منابع مشابه
Subset Sums Avoiding Quadratic Nonresidues
It is a well-known problem to give an estimate for the largest clique of the Paley-graph, i.e. , to give an estimate for |A| if A ⊂ Fp (p ≡ 1 (mod 4)) is such that A−A = {a−a′ |a, a′ ∈ A} avoids the set of quadratic nonresidues. In this paper we will study a much simpler problem namely when A− A is substituted by the set FS(A) = { ∑ εaa | εa = 0 or 1 and ∑ εa > 0}. In other words we will estima...
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If A is a finite set of cardinality n ≥ 1, 2 is the set of all subsets of A, and S is a nonempty subset of 2, we say that S has the odd-intersection property if there exists a subset N of A such that the cardinality of N ∩S is odd for each S ∈ S. Let OIP (n) denote the set of all subsets of 2 with the odd-intersection property. A nonempty set S of nonempty subsets of A is an obstruction (to the...
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ژورنال
عنوان ژورنال: Acta Arithmetica
سال: 2008
ISSN: 0065-1036,1730-6264
DOI: 10.4064/aa135-1-6