Some Best Possible Inequalities Concerning Cross-Intersecting Families
نویسندگان
چکیده
Let I be a non-empty family of a-subsets of an n-element set and 1 a non-empty family of b-subsets satisfying A A B# 0 for all A ES/, BEG. Suppose that n>a+b, baa. It is proved that in this case ~~~+~.4Y~<(~)-(" ;L1)+l holds. Various extensions of this result are proved. Two new proofs of the Hilton-Milner theorem on non-trivial intersection families are given as well.
منابع مشابه
Some Inequalities Concerning Cross-Intersecting Families
Combinatorics, Probability and Computing / Volume 7 / Issue 03 / September 1998, pp 247 260 DOI: null, Published online: 08 September 2000 Link to this article: http://journals.cambridge.org/abstract_S0963548398003575 How to cite this article: P. FRANKL and N. TOKUSHIGE (1998). Some Inequalities Concerning Cross-Intersecting Families. Combinatorics, Probability and Computing, 7, pp 247-260 Requ...
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ورودعنوان ژورنال:
- J. Comb. Theory, Ser. A
دوره 61 شماره
صفحات -
تاریخ انتشار 1992