On Subsets with Cardinalities of Intersections Divisible by a Fixed Integer
نویسندگان
چکیده
If m(n,l) denotes the maximum number of subsets of an n-element set such that the intersection of any two of them has cardinality divisible by l, then a trivial construction shows that m(n,l) ≥ 2 [n / l]. For l = 2, this was known to be essentially best possible. For l ≥ 3, we show by construction that m(n,l) 2 − [n / l] grows exponentially in n, and we provide upper bounds.
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ورودعنوان ژورنال:
- Eur. J. Comb.
دوره 4 شماره
صفحات -
تاریخ انتشار 1983