Enumerating split-pair arrangements
نویسندگان
چکیده
An arrangement of the multi-set {1,1,2,2, . . . , n, n} is said to be “split-pair” if for all i < n, between the two occurrences of i there is exactly one i + 1. We enumerate the number of split-pair arrangements and in particular show that the number of such arrangements is (−1)n+12n(22n − 1)B2n where Bi is the ith Bernoulli number. © 2007 Elsevier Inc. All rights reserved.
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ورودعنوان ژورنال:
- J. Comb. Theory, Ser. A
دوره 115 شماره
صفحات -
تاریخ انتشار 2008