Forbidding Just One Intersection
نویسندگان
چکیده
Following a conjecture of P. Erdos, we show that if 9 is a family of k-subsets of an n-set no two of which intersect in exactly I elements then for k 2 21+ 2 and n sufficiently large IF:/ < (;:‘,I:) with equality holding if and only if 9 consists of all the k-sets containing a fixed (I+ I)-set. In general we show 19) <dknmax(‘.k-‘-l), where dk is a constant depending only on k. These results are special cases of more general theorems (Theorem 2.1-2.3). (
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ورودعنوان ژورنال:
- J. Comb. Theory, Ser. A
دوره 39 شماره
صفحات -
تاریخ انتشار 1985