A major index for matchings and set partitions
نویسندگان
چکیده
منابع مشابه
A major index for matchings and set partitions
We introduce a statistic pmaj(P ) for partitions of [n], and show that it is equidistributed with cr2, the number of 2-crossings, over all partitions of [n] with given sets of minimal block elements and maximal block elements. This generalizes the classical result of equidistribution for the permutation statistics inv and maj. © 2007 Elsevier Inc. All rights reserved.
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ژورنال
عنوان ژورنال: Journal of Combinatorial Theory, Series A
سال: 2008
ISSN: 0097-3165
DOI: 10.1016/j.jcta.2007.11.003