Two-Part and k-Sperner Families: New Proofs Using Permutations
نویسندگان
چکیده
This is a paper about the beauty of the permutation method. New and shorter proofs are given for the theorem [P. L. Erdős and G. O. H. Katona, J. Combin. Theory. Ser. A, 43 (1986), pp. 58–69; S. Shahriari, Discrete Math., 162 (1996), pp. 229–238] determining all extremal two-part Sperner families and for the uniqueness of k-Sperner families of maximum size [P. Erdős, Bull. Amer. Math. Soc., 51 (1945), pp. 898–902].
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عنوان ژورنال:
- SIAM J. Discrete Math.
دوره 19 شماره
صفحات -
تاریخ انتشار 2005