***************************************************************************** * www.FindStat.org - The Combinatorial Statistic Finder * * * * Copyright (C) 2019 The FindStatCrew * * * * This information is distributed in the hope that it will be useful, * * but WITHOUT ANY WARRANTY; without even the implied warranty of * * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. * ***************************************************************************** ----------------------------------------------------------------------------- Statistic identifier: St001561 ----------------------------------------------------------------------------- Collection: Integer partitions ----------------------------------------------------------------------------- Description: The value of the elementary symmetric function evaluated at 1. The statistic is $e_\lambda(x_1,\dotsc,x_k)$ evaluated at $x_1=x_2=\dotsb=x_k=1$, where $\lambda$ has $k$ parts. Thus, the statistic is equal to $\prod_{j=1}^k \frac{(k)_{\lambda_j}}{\lambda_j!}$ where $\lambda$ has $k$ parts. ----------------------------------------------------------------------------- References: [1] Stanley, R. P. Enumerative combinatorics. Vol. 2 [[MathSciNet:1676282]] [2] Rosas, M. H. Specializations of MacMahon symmetric functions and the polynomial algebra [[DOI:10.1016/s0012-365x(01)00263-1]] ----------------------------------------------------------------------------- Code: ----------------------------------------------------------------------------- Statistic values: [1] => 1 [2] => 0 [1,1] => 4 [3] => 0 [2,1] => 2 [1,1,1] => 27 [4] => 0 [3,1] => 0 [2,2] => 1 [2,1,1] => 27 [1,1,1,1] => 256 [5] => 0 [4,1] => 0 [3,2] => 0 [3,1,1] => 9 [2,2,1] => 27 [2,1,1,1] => 384 [1,1,1,1,1] => 3125 [6] => 0 [5,1] => 0 [4,2] => 0 [4,1,1] => 0 [3,3] => 0 [3,2,1] => 9 [3,1,1,1] => 256 [2,2,2] => 27 [2,2,1,1] => 576 [2,1,1,1,1] => 6250 [1,1,1,1,1,1] => 46656 [7] => 0 [6,1] => 0 [5,2] => 0 [5,1,1] => 0 [4,3] => 0 [4,2,1] => 0 [4,1,1,1] => 64 [3,3,1] => 3 [3,2,2] => 9 [3,2,1,1] => 384 [3,1,1,1,1] => 6250 [2,2,2,1] => 864 [2,2,1,1,1] => 12500 [2,1,1,1,1,1] => 116640 [1,1,1,1,1,1,1] => 823543 ----------------------------------------------------------------------------- Created: Jul 11, 2020 at 10:12 by Per Alexandersson ----------------------------------------------------------------------------- Last Updated: Jul 11, 2020 at 10:49 by Per Alexandersson