Maximum Hitting for n Sufficiently Large
نویسنده
چکیده
For a left-compressed intersecting family A ⊆ [n] and a set X ⊆ [n], let A(X) = {A ∈ A : A ∩ X 6= ∅}. Borg asked: for which X is |A(X)| maximised by taking A to be all r-sets containing the element 1? We determine exactly which X have this property, for n sufficiently large depending on r.
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ورودعنوان ژورنال:
- Graphs and Combinatorics
دوره 30 شماره
صفحات -
تاریخ انتشار 2014