A Sperner Theorem on Unrelated Chains of Subsets
نویسندگان
چکیده
A theorem of Sperner [2] states that a collection of subsets of (l,..., n), no two ordered by inclusion, contains at most ( &,) sets. How many twoelement chains A cB of subsets of {I,..., n} can be found such that sets in different chains are not related? More generally, we seek to determinef,(n), defined to be the maximum m such that there exist subsets A(i,j) 5 {l,..., n}, 1 < i < m, 0 <j < k, satisfying
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ورودعنوان ژورنال:
- J. Comb. Theory, Ser. A
دوره 36 شماره
صفحات -
تاریخ انتشار 1984