Families intersecting on an interval
نویسنده
چکیده
We shall be interested in the following Erdős-Ko-Rado-type question. Fix some set B ⊂ [n]. How large a family A ⊂ P [n] can we find such that the intersection of any two sets in A contains a cyclic translate (modulo n) of B? Chung, Graham, Frankl and Shearer have proved that, in the case where B is a block of length t, we can do no better than to take A to consist of all supersets of B. We give an alternative proof of this result, which is in a certain sense more ‘direct’.
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عنوان ژورنال:
- Discrete Mathematics
دوره 309 شماره
صفحات -
تاریخ انتشار 2009