Pairs of Disjoint q-element Subsets Far from Each Other
نویسندگان
چکیده
Let n and q be given integers and X a finite set with n elements. The following theorem is proved for n > n0(q). The family of all q-element subsets of X can be partitioned into disjoint pairs (except possibly one if (n q ) is odd), so that |A1∩A2|+ |B1 ∩B2| ≤ q, |A1 ∩B2|+ |B1 ∩A2| ≤ q holds for any two such pairs {A1, B1} and {A2, B2}. This is a sharpening of a theorem in [2]. It is also shown that this is a coding type problem, and several problems of similar nature are posed.
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ورودعنوان ژورنال:
- Electr. J. Comb.
دوره 8 شماره
صفحات -
تاریخ انتشار 2001