***************************************************************************** * 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: St001627 ----------------------------------------------------------------------------- Collection: Integer partitions ----------------------------------------------------------------------------- Description: The number of coloured connected graphs such that the multiplicities of colours are given by a partition. In particular, the value on the partition $(n)$ is the number of unlabelled connected graphs on $n$ vertices, [[oeis:A001349]], whereas the value on the partition $(1^n)$ is the number of labelled connected graphs [[oeis:A001187]]. ----------------------------------------------------------------------------- References: ----------------------------------------------------------------------------- Code: def statistic(mu): h = SymmetricFunctions(QQ).h() F = (species.SimpleGraphSpecies().cycle_index_series()-1).logarithm() return F.coefficient(mu.size()).scalar(h(mu)) ----------------------------------------------------------------------------- Statistic values: [1] => 1 [2] => 1 [1,1] => 1 [3] => 2 [2,1] => 3 [1,1,1] => 4 [4] => 6 [3,1] => 11 [2,2] => 16 [2,1,1] => 23 [1,1,1,1] => 38 [5] => 21 [4,1] => 58 [3,2] => 98 [3,1,1] => 162 [2,2,1] => 230 [2,1,1,1] => 402 [1,1,1,1,1] => 728 [6] => 112 [5,1] => 407 [4,2] => 879 [4,1,1] => 1549 [3,3] => 1087 [3,2,1] => 2812 [3,1,1,1] => 5204 [2,2,2] => 4065 [2,2,1,1] => 7490 [2,1,1,1,1] => 14080 [1,1,1,1,1,1] => 26704 ----------------------------------------------------------------------------- Created: Oct 01, 2020 at 22:08 by Martin Rubey ----------------------------------------------------------------------------- Last Updated: Oct 01, 2020 at 22:08 by Martin Rubey