An Inequality for Kruskal-macaulay Functions

نویسندگان

  • BERNARDO M. ÁBREGO
  • SILVIA FERNÁNDEZ-MERCHANT
چکیده

for some N ≥ k + 1, then the equality in (1.2) occurs only when a = 0. Kruskal-Macaulay functions are relevant for their applications to the study of antichains in multisets (see for example [11, 2]), posets, rings and polyhedral combinatorics (see [5] and the survey [3]). In particular, they play and important role in proving results, extensions and generalizations of classical problems concerning the Kruskal-Katona [12, 10, 15], Macaulay [13], and Erdős-Ko-Rado [9] theorems. More recently, the authors [1], applied Theorem 1 to the problem of finding the maximum number of translated copies of a pattern that can

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تاریخ انتشار 2009