*****************************************************************************
*       www.FindStat.org - The Combinatorial Statistic Finder               *
*                                                                           *
*       Copyright (C) 2019 The FindStatCrew <info@findstat.org>             *
*                                                                           *
*    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: St000021

-----------------------------------------------------------------------------
Collection: Permutations

-----------------------------------------------------------------------------
Description: The number of descents of a permutation.

This can be described as an occurrence of the vincular mesh pattern ([2,1], {(1,0),(1,1),(1,2)}), i.e., the middle column is shaded, see [3].

-----------------------------------------------------------------------------
References: [1]   [[/Permutations/Descents]]
[2]   Triangle of Eulerian numbers T(n,k) (n>=1, 1 <= k <= n) read by rows. [[OEIS:A008292]]
[3]   BrändÊn, P., Claesson, A. Mesh patterns and the expansion of permutation statistics as sums of permutation patterns [[arXiv:1102.4226]]

-----------------------------------------------------------------------------
Code:
def statistic(x):
    return x.number_of_descents()

-----------------------------------------------------------------------------
Statistic values:

[]            => 0
[1]           => 0
[1,2]         => 0
[2,1]         => 1
[1,2,3]       => 0
[1,3,2]       => 1
[2,1,3]       => 1
[2,3,1]       => 1
[3,1,2]       => 1
[3,2,1]       => 2
[1,2,3,4]     => 0
[1,2,4,3]     => 1
[1,3,2,4]     => 1
[1,3,4,2]     => 1
[1,4,2,3]     => 1
[1,4,3,2]     => 2
[2,1,3,4]     => 1
[2,1,4,3]     => 2
[2,3,1,4]     => 1
[2,3,4,1]     => 1
[2,4,1,3]     => 1
[2,4,3,1]     => 2
[3,1,2,4]     => 1
[3,1,4,2]     => 2
[3,2,1,4]     => 2
[3,2,4,1]     => 2
[3,4,1,2]     => 1
[3,4,2,1]     => 2
[4,1,2,3]     => 1
[4,1,3,2]     => 2
[4,2,1,3]     => 2
[4,2,3,1]     => 2
[4,3,1,2]     => 2
[4,3,2,1]     => 3
[1,2,3,4,5]   => 0
[1,2,3,5,4]   => 1
[1,2,4,3,5]   => 1
[1,2,4,5,3]   => 1
[1,2,5,3,4]   => 1
[1,2,5,4,3]   => 2
[1,3,2,4,5]   => 1
[1,3,2,5,4]   => 2
[1,3,4,2,5]   => 1
[1,3,4,5,2]   => 1
[1,3,5,2,4]   => 1
[1,3,5,4,2]   => 2
[1,4,2,3,5]   => 1
[1,4,2,5,3]   => 2
[1,4,3,2,5]   => 2
[1,4,3,5,2]   => 2
[1,4,5,2,3]   => 1
[1,4,5,3,2]   => 2
[1,5,2,3,4]   => 1
[1,5,2,4,3]   => 2
[1,5,3,2,4]   => 2
[1,5,3,4,2]   => 2
[1,5,4,2,3]   => 2
[1,5,4,3,2]   => 3
[2,1,3,4,5]   => 1
[2,1,3,5,4]   => 2
[2,1,4,3,5]   => 2
[2,1,4,5,3]   => 2
[2,1,5,3,4]   => 2
[2,1,5,4,3]   => 3
[2,3,1,4,5]   => 1
[2,3,1,5,4]   => 2
[2,3,4,1,5]   => 1
[2,3,4,5,1]   => 1
[2,3,5,1,4]   => 1
[2,3,5,4,1]   => 2
[2,4,1,3,5]   => 1
[2,4,1,5,3]   => 2
[2,4,3,1,5]   => 2
[2,4,3,5,1]   => 2
[2,4,5,1,3]   => 1
[2,4,5,3,1]   => 2
[2,5,1,3,4]   => 1
[2,5,1,4,3]   => 2
[2,5,3,1,4]   => 2
[2,5,3,4,1]   => 2
[2,5,4,1,3]   => 2
[2,5,4,3,1]   => 3
[3,1,2,4,5]   => 1
[3,1,2,5,4]   => 2
[3,1,4,2,5]   => 2
[3,1,4,5,2]   => 2
[3,1,5,2,4]   => 2
[3,1,5,4,2]   => 3
[3,2,1,4,5]   => 2
[3,2,1,5,4]   => 3
[3,2,4,1,5]   => 2
[3,2,4,5,1]   => 2
[3,2,5,1,4]   => 2
[3,2,5,4,1]   => 3
[3,4,1,2,5]   => 1
[3,4,1,5,2]   => 2
[3,4,2,1,5]   => 2
[3,4,2,5,1]   => 2
[3,4,5,1,2]   => 1
[3,4,5,2,1]   => 2
[3,5,1,2,4]   => 1
[3,5,1,4,2]   => 2
[3,5,2,1,4]   => 2
[3,5,2,4,1]   => 2
[3,5,4,1,2]   => 2
[3,5,4,2,1]   => 3
[4,1,2,3,5]   => 1
[4,1,2,5,3]   => 2
[4,1,3,2,5]   => 2
[4,1,3,5,2]   => 2
[4,1,5,2,3]   => 2
[4,1,5,3,2]   => 3
[4,2,1,3,5]   => 2
[4,2,1,5,3]   => 3
[4,2,3,1,5]   => 2
[4,2,3,5,1]   => 2
[4,2,5,1,3]   => 2
[4,2,5,3,1]   => 3
[4,3,1,2,5]   => 2
[4,3,1,5,2]   => 3
[4,3,2,1,5]   => 3
[4,3,2,5,1]   => 3
[4,3,5,1,2]   => 2
[4,3,5,2,1]   => 3
[4,5,1,2,3]   => 1
[4,5,1,3,2]   => 2
[4,5,2,1,3]   => 2
[4,5,2,3,1]   => 2
[4,5,3,1,2]   => 2
[4,5,3,2,1]   => 3
[5,1,2,3,4]   => 1
[5,1,2,4,3]   => 2
[5,1,3,2,4]   => 2
[5,1,3,4,2]   => 2
[5,1,4,2,3]   => 2
[5,1,4,3,2]   => 3
[5,2,1,3,4]   => 2
[5,2,1,4,3]   => 3
[5,2,3,1,4]   => 2
[5,2,3,4,1]   => 2
[5,2,4,1,3]   => 2
[5,2,4,3,1]   => 3
[5,3,1,2,4]   => 2
[5,3,1,4,2]   => 3
[5,3,2,1,4]   => 3
[5,3,2,4,1]   => 3
[5,3,4,1,2]   => 2
[5,3,4,2,1]   => 3
[5,4,1,2,3]   => 2
[5,4,1,3,2]   => 3
[5,4,2,1,3]   => 3
[5,4,2,3,1]   => 3
[5,4,3,1,2]   => 3
[5,4,3,2,1]   => 4
[1,2,3,4,5,6] => 0
[1,2,3,4,6,5] => 1
[1,2,3,5,4,6] => 1
[1,2,3,5,6,4] => 1
[1,2,3,6,4,5] => 1
[1,2,3,6,5,4] => 2
[1,2,4,3,5,6] => 1
[1,2,4,3,6,5] => 2
[1,2,4,5,3,6] => 1
[1,2,4,5,6,3] => 1
[1,2,4,6,3,5] => 1
[1,2,4,6,5,3] => 2
[1,2,5,3,4,6] => 1
[1,2,5,3,6,4] => 2
[1,2,5,4,3,6] => 2
[1,2,5,4,6,3] => 2
[1,2,5,6,3,4] => 1
[1,2,5,6,4,3] => 2
[1,2,6,3,4,5] => 1
[1,2,6,3,5,4] => 2
[1,2,6,4,3,5] => 2
[1,2,6,4,5,3] => 2
[1,2,6,5,3,4] => 2
[1,2,6,5,4,3] => 3
[1,3,2,4,5,6] => 1
[1,3,2,4,6,5] => 2
[1,3,2,5,4,6] => 2
[1,3,2,5,6,4] => 2
[1,3,2,6,4,5] => 2
[1,3,2,6,5,4] => 3
[1,3,4,2,5,6] => 1
[1,3,4,2,6,5] => 2
[1,3,4,5,2,6] => 1
[1,3,4,5,6,2] => 1
[1,3,4,6,2,5] => 1
[1,3,4,6,5,2] => 2
[1,3,5,2,4,6] => 1
[1,3,5,2,6,4] => 2
[1,3,5,4,2,6] => 2
[1,3,5,4,6,2] => 2
[1,3,5,6,2,4] => 1
[1,3,5,6,4,2] => 2
[1,3,6,2,4,5] => 1
[1,3,6,2,5,4] => 2
[1,3,6,4,2,5] => 2
[1,3,6,4,5,2] => 2
[1,3,6,5,2,4] => 2
[1,3,6,5,4,2] => 3
[1,4,2,3,5,6] => 1
[1,4,2,3,6,5] => 2
[1,4,2,5,3,6] => 2
[1,4,2,5,6,3] => 2
[1,4,2,6,3,5] => 2
[1,4,2,6,5,3] => 3
[1,4,3,2,5,6] => 2
[1,4,3,2,6,5] => 3
[1,4,3,5,2,6] => 2
[1,4,3,5,6,2] => 2
[1,4,3,6,2,5] => 2
[1,4,3,6,5,2] => 3
[1,4,5,2,3,6] => 1
[1,4,5,2,6,3] => 2
[1,4,5,3,2,6] => 2
[1,4,5,3,6,2] => 2
[1,4,5,6,2,3] => 1
[1,4,5,6,3,2] => 2
[1,4,6,2,3,5] => 1
[1,4,6,2,5,3] => 2
[1,4,6,3,2,5] => 2
[1,4,6,3,5,2] => 2
[1,4,6,5,2,3] => 2
[1,4,6,5,3,2] => 3
[1,5,2,3,4,6] => 1
[1,5,2,3,6,4] => 2
[1,5,2,4,3,6] => 2
[1,5,2,4,6,3] => 2
[1,5,2,6,3,4] => 2
[1,5,2,6,4,3] => 3
[1,5,3,2,4,6] => 2
[1,5,3,2,6,4] => 3
[1,5,3,4,2,6] => 2
[1,5,3,4,6,2] => 2
[1,5,3,6,2,4] => 2
[1,5,3,6,4,2] => 3
[1,5,4,2,3,6] => 2
[1,5,4,2,6,3] => 3
[1,5,4,3,2,6] => 3
[1,5,4,3,6,2] => 3
[1,5,4,6,2,3] => 2
[1,5,4,6,3,2] => 3
[1,5,6,2,3,4] => 1
[1,5,6,2,4,3] => 2
[1,5,6,3,2,4] => 2
[1,5,6,3,4,2] => 2
[1,5,6,4,2,3] => 2
[1,5,6,4,3,2] => 3
[1,6,2,3,4,5] => 1
[1,6,2,3,5,4] => 2
[1,6,2,4,3,5] => 2
[1,6,2,4,5,3] => 2
[1,6,2,5,3,4] => 2
[1,6,2,5,4,3] => 3
[1,6,3,2,4,5] => 2
[1,6,3,2,5,4] => 3
[1,6,3,4,2,5] => 2
[1,6,3,4,5,2] => 2
[1,6,3,5,2,4] => 2
[1,6,3,5,4,2] => 3
[1,6,4,2,3,5] => 2
[1,6,4,2,5,3] => 3
[1,6,4,3,2,5] => 3
[1,6,4,3,5,2] => 3
[1,6,4,5,2,3] => 2
[1,6,4,5,3,2] => 3
[1,6,5,2,3,4] => 2
[1,6,5,2,4,3] => 3
[1,6,5,3,2,4] => 3
[1,6,5,3,4,2] => 3
[1,6,5,4,2,3] => 3
[1,6,5,4,3,2] => 4
[2,1,3,4,5,6] => 1
[2,1,3,4,6,5] => 2
[2,1,3,5,4,6] => 2
[2,1,3,5,6,4] => 2
[2,1,3,6,4,5] => 2
[2,1,3,6,5,4] => 3
[2,1,4,3,5,6] => 2
[2,1,4,3,6,5] => 3
[2,1,4,5,3,6] => 2
[2,1,4,5,6,3] => 2
[2,1,4,6,3,5] => 2
[2,1,4,6,5,3] => 3
[2,1,5,3,4,6] => 2
[2,1,5,3,6,4] => 3
[2,1,5,4,3,6] => 3
[2,1,5,4,6,3] => 3
[2,1,5,6,3,4] => 2
[2,1,5,6,4,3] => 3
[2,1,6,3,4,5] => 2
[2,1,6,3,5,4] => 3
[2,1,6,4,3,5] => 3
[2,1,6,4,5,3] => 3
[2,1,6,5,3,4] => 3
[2,1,6,5,4,3] => 4
[2,3,1,4,5,6] => 1
[2,3,1,4,6,5] => 2
[2,3,1,5,4,6] => 2
[2,3,1,5,6,4] => 2
[2,3,1,6,4,5] => 2
[2,3,1,6,5,4] => 3
[2,3,4,1,5,6] => 1
[2,3,4,1,6,5] => 2
[2,3,4,5,1,6] => 1
[2,3,4,5,6,1] => 1
[2,3,4,6,1,5] => 1
[2,3,4,6,5,1] => 2
[2,3,5,1,4,6] => 1
[2,3,5,1,6,4] => 2
[2,3,5,4,1,6] => 2
[2,3,5,4,6,1] => 2
[2,3,5,6,1,4] => 1
[2,3,5,6,4,1] => 2
[2,3,6,1,4,5] => 1
[2,3,6,1,5,4] => 2
[2,3,6,4,1,5] => 2
[2,3,6,4,5,1] => 2
[2,3,6,5,1,4] => 2
[2,3,6,5,4,1] => 3
[2,4,1,3,5,6] => 1
[2,4,1,3,6,5] => 2
[2,4,1,5,3,6] => 2
[2,4,1,5,6,3] => 2
[2,4,1,6,3,5] => 2
[2,4,1,6,5,3] => 3
[2,4,3,1,5,6] => 2
[2,4,3,1,6,5] => 3
[2,4,3,5,1,6] => 2
[2,4,3,5,6,1] => 2
[2,4,3,6,1,5] => 2
[2,4,3,6,5,1] => 3
[2,4,5,1,3,6] => 1
[2,4,5,1,6,3] => 2
[2,4,5,3,1,6] => 2
[2,4,5,3,6,1] => 2
[2,4,5,6,1,3] => 1
[2,4,5,6,3,1] => 2
[2,4,6,1,3,5] => 1
[2,4,6,1,5,3] => 2
[2,4,6,3,1,5] => 2
[2,4,6,3,5,1] => 2
[2,4,6,5,1,3] => 2
[2,4,6,5,3,1] => 3
[2,5,1,3,4,6] => 1
[2,5,1,3,6,4] => 2
[2,5,1,4,3,6] => 2
[2,5,1,4,6,3] => 2
[2,5,1,6,3,4] => 2
[2,5,1,6,4,3] => 3
[2,5,3,1,4,6] => 2
[2,5,3,1,6,4] => 3
[2,5,3,4,1,6] => 2
[2,5,3,4,6,1] => 2
[2,5,3,6,1,4] => 2
[2,5,3,6,4,1] => 3
[2,5,4,1,3,6] => 2
[2,5,4,1,6,3] => 3
[2,5,4,3,1,6] => 3
[2,5,4,3,6,1] => 3
[2,5,4,6,1,3] => 2
[2,5,4,6,3,1] => 3
[2,5,6,1,3,4] => 1
[2,5,6,1,4,3] => 2
[2,5,6,3,1,4] => 2
[2,5,6,3,4,1] => 2
[2,5,6,4,1,3] => 2
[2,5,6,4,3,1] => 3
[2,6,1,3,4,5] => 1
[2,6,1,3,5,4] => 2
[2,6,1,4,3,5] => 2
[2,6,1,4,5,3] => 2
[2,6,1,5,3,4] => 2
[2,6,1,5,4,3] => 3
[2,6,3,1,4,5] => 2
[2,6,3,1,5,4] => 3
[2,6,3,4,1,5] => 2
[2,6,3,4,5,1] => 2
[2,6,3,5,1,4] => 2
[2,6,3,5,4,1] => 3
[2,6,4,1,3,5] => 2
[2,6,4,1,5,3] => 3
[2,6,4,3,1,5] => 3
[2,6,4,3,5,1] => 3
[2,6,4,5,1,3] => 2
[2,6,4,5,3,1] => 3
[2,6,5,1,3,4] => 2
[2,6,5,1,4,3] => 3
[2,6,5,3,1,4] => 3
[2,6,5,3,4,1] => 3
[2,6,5,4,1,3] => 3
[2,6,5,4,3,1] => 4
[3,1,2,4,5,6] => 1
[3,1,2,4,6,5] => 2
[3,1,2,5,4,6] => 2
[3,1,2,5,6,4] => 2
[3,1,2,6,4,5] => 2
[3,1,2,6,5,4] => 3
[3,1,4,2,5,6] => 2
[3,1,4,2,6,5] => 3
[3,1,4,5,2,6] => 2
[3,1,4,5,6,2] => 2
[3,1,4,6,2,5] => 2
[3,1,4,6,5,2] => 3
[3,1,5,2,4,6] => 2
[3,1,5,2,6,4] => 3
[3,1,5,4,2,6] => 3
[3,1,5,4,6,2] => 3
[3,1,5,6,2,4] => 2
[3,1,5,6,4,2] => 3
[3,1,6,2,4,5] => 2
[3,1,6,2,5,4] => 3
[3,1,6,4,2,5] => 3
[3,1,6,4,5,2] => 3
[3,1,6,5,2,4] => 3
[3,1,6,5,4,2] => 4
[3,2,1,4,5,6] => 2
[3,2,1,4,6,5] => 3
[3,2,1,5,4,6] => 3
[3,2,1,5,6,4] => 3
[3,2,1,6,4,5] => 3
[3,2,1,6,5,4] => 4
[3,2,4,1,5,6] => 2
[3,2,4,1,6,5] => 3
[3,2,4,5,1,6] => 2
[3,2,4,5,6,1] => 2
[3,2,4,6,1,5] => 2
[3,2,4,6,5,1] => 3
[3,2,5,1,4,6] => 2
[3,2,5,1,6,4] => 3
[3,2,5,4,1,6] => 3
[3,2,5,4,6,1] => 3
[3,2,5,6,1,4] => 2
[3,2,5,6,4,1] => 3
[3,2,6,1,4,5] => 2
[3,2,6,1,5,4] => 3
[3,2,6,4,1,5] => 3
[3,2,6,4,5,1] => 3
[3,2,6,5,1,4] => 3
[3,2,6,5,4,1] => 4
[3,4,1,2,5,6] => 1
[3,4,1,2,6,5] => 2
[3,4,1,5,2,6] => 2
[3,4,1,5,6,2] => 2
[3,4,1,6,2,5] => 2
[3,4,1,6,5,2] => 3
[3,4,2,1,5,6] => 2
[3,4,2,1,6,5] => 3
[3,4,2,5,1,6] => 2
[3,4,2,5,6,1] => 2
[3,4,2,6,1,5] => 2
[3,4,2,6,5,1] => 3
[3,4,5,1,2,6] => 1
[3,4,5,1,6,2] => 2
[3,4,5,2,1,6] => 2
[3,4,5,2,6,1] => 2
[3,4,5,6,1,2] => 1
[3,4,5,6,2,1] => 2
[3,4,6,1,2,5] => 1
[3,4,6,1,5,2] => 2
[3,4,6,2,1,5] => 2
[3,4,6,2,5,1] => 2
[3,4,6,5,1,2] => 2
[3,4,6,5,2,1] => 3
[3,5,1,2,4,6] => 1
[3,5,1,2,6,4] => 2
[3,5,1,4,2,6] => 2
[3,5,1,4,6,2] => 2
[3,5,1,6,2,4] => 2
[3,5,1,6,4,2] => 3
[3,5,2,1,4,6] => 2
[3,5,2,1,6,4] => 3
[3,5,2,4,1,6] => 2
[3,5,2,4,6,1] => 2
[3,5,2,6,1,4] => 2
[3,5,2,6,4,1] => 3
[3,5,4,1,2,6] => 2
[3,5,4,1,6,2] => 3
[3,5,4,2,1,6] => 3
[3,5,4,2,6,1] => 3
[3,5,4,6,1,2] => 2
[3,5,4,6,2,1] => 3
[3,5,6,1,2,4] => 1
[3,5,6,1,4,2] => 2
[3,5,6,2,1,4] => 2
[3,5,6,2,4,1] => 2
[3,5,6,4,1,2] => 2
[3,5,6,4,2,1] => 3
[3,6,1,2,4,5] => 1
[3,6,1,2,5,4] => 2
[3,6,1,4,2,5] => 2
[3,6,1,4,5,2] => 2
[3,6,1,5,2,4] => 2
[3,6,1,5,4,2] => 3
[3,6,2,1,4,5] => 2
[3,6,2,1,5,4] => 3
[3,6,2,4,1,5] => 2
[3,6,2,4,5,1] => 2
[3,6,2,5,1,4] => 2
[3,6,2,5,4,1] => 3
[3,6,4,1,2,5] => 2
[3,6,4,1,5,2] => 3
[3,6,4,2,1,5] => 3
[3,6,4,2,5,1] => 3
[3,6,4,5,1,2] => 2
[3,6,4,5,2,1] => 3
[3,6,5,1,2,4] => 2
[3,6,5,1,4,2] => 3
[3,6,5,2,1,4] => 3
[3,6,5,2,4,1] => 3
[3,6,5,4,1,2] => 3
[3,6,5,4,2,1] => 4
[4,1,2,3,5,6] => 1
[4,1,2,3,6,5] => 2
[4,1,2,5,3,6] => 2
[4,1,2,5,6,3] => 2
[4,1,2,6,3,5] => 2
[4,1,2,6,5,3] => 3
[4,1,3,2,5,6] => 2
[4,1,3,2,6,5] => 3
[4,1,3,5,2,6] => 2
[4,1,3,5,6,2] => 2
[4,1,3,6,2,5] => 2
[4,1,3,6,5,2] => 3
[4,1,5,2,3,6] => 2
[4,1,5,2,6,3] => 3
[4,1,5,3,2,6] => 3
[4,1,5,3,6,2] => 3
[4,1,5,6,2,3] => 2
[4,1,5,6,3,2] => 3
[4,1,6,2,3,5] => 2
[4,1,6,2,5,3] => 3
[4,1,6,3,2,5] => 3
[4,1,6,3,5,2] => 3
[4,1,6,5,2,3] => 3
[4,1,6,5,3,2] => 4
[4,2,1,3,5,6] => 2
[4,2,1,3,6,5] => 3
[4,2,1,5,3,6] => 3
[4,2,1,5,6,3] => 3
[4,2,1,6,3,5] => 3
[4,2,1,6,5,3] => 4
[4,2,3,1,5,6] => 2
[4,2,3,1,6,5] => 3
[4,2,3,5,1,6] => 2
[4,2,3,5,6,1] => 2
[4,2,3,6,1,5] => 2
[4,2,3,6,5,1] => 3
[4,2,5,1,3,6] => 2
[4,2,5,1,6,3] => 3
[4,2,5,3,1,6] => 3
[4,2,5,3,6,1] => 3
[4,2,5,6,1,3] => 2
[4,2,5,6,3,1] => 3
[4,2,6,1,3,5] => 2
[4,2,6,1,5,3] => 3
[4,2,6,3,1,5] => 3
[4,2,6,3,5,1] => 3
[4,2,6,5,1,3] => 3
[4,2,6,5,3,1] => 4
[4,3,1,2,5,6] => 2
[4,3,1,2,6,5] => 3
[4,3,1,5,2,6] => 3
[4,3,1,5,6,2] => 3
[4,3,1,6,2,5] => 3
[4,3,1,6,5,2] => 4
[4,3,2,1,5,6] => 3
[4,3,2,1,6,5] => 4
[4,3,2,5,1,6] => 3
[4,3,2,5,6,1] => 3
[4,3,2,6,1,5] => 3
[4,3,2,6,5,1] => 4
[4,3,5,1,2,6] => 2
[4,3,5,1,6,2] => 3
[4,3,5,2,1,6] => 3
[4,3,5,2,6,1] => 3
[4,3,5,6,1,2] => 2
[4,3,5,6,2,1] => 3
[4,3,6,1,2,5] => 2
[4,3,6,1,5,2] => 3
[4,3,6,2,1,5] => 3
[4,3,6,2,5,1] => 3
[4,3,6,5,1,2] => 3
[4,3,6,5,2,1] => 4
[4,5,1,2,3,6] => 1
[4,5,1,2,6,3] => 2
[4,5,1,3,2,6] => 2
[4,5,1,3,6,2] => 2
[4,5,1,6,2,3] => 2
[4,5,1,6,3,2] => 3
[4,5,2,1,3,6] => 2
[4,5,2,1,6,3] => 3
[4,5,2,3,1,6] => 2
[4,5,2,3,6,1] => 2
[4,5,2,6,1,3] => 2
[4,5,2,6,3,1] => 3
[4,5,3,1,2,6] => 2
[4,5,3,1,6,2] => 3
[4,5,3,2,1,6] => 3
[4,5,3,2,6,1] => 3
[4,5,3,6,1,2] => 2
[4,5,3,6,2,1] => 3
[4,5,6,1,2,3] => 1
[4,5,6,1,3,2] => 2
[4,5,6,2,1,3] => 2
[4,5,6,2,3,1] => 2
[4,5,6,3,1,2] => 2
[4,5,6,3,2,1] => 3
[4,6,1,2,3,5] => 1
[4,6,1,2,5,3] => 2
[4,6,1,3,2,5] => 2
[4,6,1,3,5,2] => 2
[4,6,1,5,2,3] => 2
[4,6,1,5,3,2] => 3
[4,6,2,1,3,5] => 2
[4,6,2,1,5,3] => 3
[4,6,2,3,1,5] => 2
[4,6,2,3,5,1] => 2
[4,6,2,5,1,3] => 2
[4,6,2,5,3,1] => 3
[4,6,3,1,2,5] => 2
[4,6,3,1,5,2] => 3
[4,6,3,2,1,5] => 3
[4,6,3,2,5,1] => 3
[4,6,3,5,1,2] => 2
[4,6,3,5,2,1] => 3
[4,6,5,1,2,3] => 2
[4,6,5,1,3,2] => 3
[4,6,5,2,1,3] => 3
[4,6,5,2,3,1] => 3
[4,6,5,3,1,2] => 3
[4,6,5,3,2,1] => 4
[5,1,2,3,4,6] => 1
[5,1,2,3,6,4] => 2
[5,1,2,4,3,6] => 2
[5,1,2,4,6,3] => 2
[5,1,2,6,3,4] => 2
[5,1,2,6,4,3] => 3
[5,1,3,2,4,6] => 2
[5,1,3,2,6,4] => 3
[5,1,3,4,2,6] => 2
[5,1,3,4,6,2] => 2
[5,1,3,6,2,4] => 2
[5,1,3,6,4,2] => 3
[5,1,4,2,3,6] => 2
[5,1,4,2,6,3] => 3
[5,1,4,3,2,6] => 3
[5,1,4,3,6,2] => 3
[5,1,4,6,2,3] => 2
[5,1,4,6,3,2] => 3
[5,1,6,2,3,4] => 2
[5,1,6,2,4,3] => 3
[5,1,6,3,2,4] => 3
[5,1,6,3,4,2] => 3
[5,1,6,4,2,3] => 3
[5,1,6,4,3,2] => 4
[5,2,1,3,4,6] => 2
[5,2,1,3,6,4] => 3
[5,2,1,4,3,6] => 3
[5,2,1,4,6,3] => 3
[5,2,1,6,3,4] => 3
[5,2,1,6,4,3] => 4
[5,2,3,1,4,6] => 2
[5,2,3,1,6,4] => 3
[5,2,3,4,1,6] => 2
[5,2,3,4,6,1] => 2
[5,2,3,6,1,4] => 2
[5,2,3,6,4,1] => 3
[5,2,4,1,3,6] => 2
[5,2,4,1,6,3] => 3
[5,2,4,3,1,6] => 3
[5,2,4,3,6,1] => 3
[5,2,4,6,1,3] => 2
[5,2,4,6,3,1] => 3
[5,2,6,1,3,4] => 2
[5,2,6,1,4,3] => 3
[5,2,6,3,1,4] => 3
[5,2,6,3,4,1] => 3
[5,2,6,4,1,3] => 3
[5,2,6,4,3,1] => 4
[5,3,1,2,4,6] => 2
[5,3,1,2,6,4] => 3
[5,3,1,4,2,6] => 3
[5,3,1,4,6,2] => 3
[5,3,1,6,2,4] => 3
[5,3,1,6,4,2] => 4
[5,3,2,1,4,6] => 3
[5,3,2,1,6,4] => 4
[5,3,2,4,1,6] => 3
[5,3,2,4,6,1] => 3
[5,3,2,6,1,4] => 3
[5,3,2,6,4,1] => 4
[5,3,4,1,2,6] => 2
[5,3,4,1,6,2] => 3
[5,3,4,2,1,6] => 3
[5,3,4,2,6,1] => 3
[5,3,4,6,1,2] => 2
[5,3,4,6,2,1] => 3
[5,3,6,1,2,4] => 2
[5,3,6,1,4,2] => 3
[5,3,6,2,1,4] => 3
[5,3,6,2,4,1] => 3
[5,3,6,4,1,2] => 3
[5,3,6,4,2,1] => 4
[5,4,1,2,3,6] => 2
[5,4,1,2,6,3] => 3
[5,4,1,3,2,6] => 3
[5,4,1,3,6,2] => 3
[5,4,1,6,2,3] => 3
[5,4,1,6,3,2] => 4
[5,4,2,1,3,6] => 3
[5,4,2,1,6,3] => 4
[5,4,2,3,1,6] => 3
[5,4,2,3,6,1] => 3
[5,4,2,6,1,3] => 3
[5,4,2,6,3,1] => 4
[5,4,3,1,2,6] => 3
[5,4,3,1,6,2] => 4
[5,4,3,2,1,6] => 4
[5,4,3,2,6,1] => 4
[5,4,3,6,1,2] => 3
[5,4,3,6,2,1] => 4
[5,4,6,1,2,3] => 2
[5,4,6,1,3,2] => 3
[5,4,6,2,1,3] => 3
[5,4,6,2,3,1] => 3
[5,4,6,3,1,2] => 3
[5,4,6,3,2,1] => 4
[5,6,1,2,3,4] => 1
[5,6,1,2,4,3] => 2
[5,6,1,3,2,4] => 2
[5,6,1,3,4,2] => 2
[5,6,1,4,2,3] => 2
[5,6,1,4,3,2] => 3
[5,6,2,1,3,4] => 2
[5,6,2,1,4,3] => 3
[5,6,2,3,1,4] => 2
[5,6,2,3,4,1] => 2
[5,6,2,4,1,3] => 2
[5,6,2,4,3,1] => 3
[5,6,3,1,2,4] => 2
[5,6,3,1,4,2] => 3
[5,6,3,2,1,4] => 3
[5,6,3,2,4,1] => 3
[5,6,3,4,1,2] => 2
[5,6,3,4,2,1] => 3
[5,6,4,1,2,3] => 2
[5,6,4,1,3,2] => 3
[5,6,4,2,1,3] => 3
[5,6,4,2,3,1] => 3
[5,6,4,3,1,2] => 3
[5,6,4,3,2,1] => 4
[6,1,2,3,4,5] => 1
[6,1,2,3,5,4] => 2
[6,1,2,4,3,5] => 2
[6,1,2,4,5,3] => 2
[6,1,2,5,3,4] => 2
[6,1,2,5,4,3] => 3
[6,1,3,2,4,5] => 2
[6,1,3,2,5,4] => 3
[6,1,3,4,2,5] => 2
[6,1,3,4,5,2] => 2
[6,1,3,5,2,4] => 2
[6,1,3,5,4,2] => 3
[6,1,4,2,3,5] => 2
[6,1,4,2,5,3] => 3
[6,1,4,3,2,5] => 3
[6,1,4,3,5,2] => 3
[6,1,4,5,2,3] => 2
[6,1,4,5,3,2] => 3
[6,1,5,2,3,4] => 2
[6,1,5,2,4,3] => 3
[6,1,5,3,2,4] => 3
[6,1,5,3,4,2] => 3
[6,1,5,4,2,3] => 3
[6,1,5,4,3,2] => 4
[6,2,1,3,4,5] => 2
[6,2,1,3,5,4] => 3
[6,2,1,4,3,5] => 3
[6,2,1,4,5,3] => 3
[6,2,1,5,3,4] => 3
[6,2,1,5,4,3] => 4
[6,2,3,1,4,5] => 2
[6,2,3,1,5,4] => 3
[6,2,3,4,1,5] => 2
[6,2,3,4,5,1] => 2
[6,2,3,5,1,4] => 2
[6,2,3,5,4,1] => 3
[6,2,4,1,3,5] => 2
[6,2,4,1,5,3] => 3
[6,2,4,3,1,5] => 3
[6,2,4,3,5,1] => 3
[6,2,4,5,1,3] => 2
[6,2,4,5,3,1] => 3
[6,2,5,1,3,4] => 2
[6,2,5,1,4,3] => 3
[6,2,5,3,1,4] => 3
[6,2,5,3,4,1] => 3
[6,2,5,4,1,3] => 3
[6,2,5,4,3,1] => 4
[6,3,1,2,4,5] => 2
[6,3,1,2,5,4] => 3
[6,3,1,4,2,5] => 3
[6,3,1,4,5,2] => 3
[6,3,1,5,2,4] => 3
[6,3,1,5,4,2] => 4
[6,3,2,1,4,5] => 3
[6,3,2,1,5,4] => 4
[6,3,2,4,1,5] => 3
[6,3,2,4,5,1] => 3
[6,3,2,5,1,4] => 3
[6,3,2,5,4,1] => 4
[6,3,4,1,2,5] => 2
[6,3,4,1,5,2] => 3
[6,3,4,2,1,5] => 3
[6,3,4,2,5,1] => 3
[6,3,4,5,1,2] => 2
[6,3,4,5,2,1] => 3
[6,3,5,1,2,4] => 2
[6,3,5,1,4,2] => 3
[6,3,5,2,1,4] => 3
[6,3,5,2,4,1] => 3
[6,3,5,4,1,2] => 3
[6,3,5,4,2,1] => 4
[6,4,1,2,3,5] => 2
[6,4,1,2,5,3] => 3
[6,4,1,3,2,5] => 3
[6,4,1,3,5,2] => 3
[6,4,1,5,2,3] => 3
[6,4,1,5,3,2] => 4
[6,4,2,1,3,5] => 3
[6,4,2,1,5,3] => 4
[6,4,2,3,1,5] => 3
[6,4,2,3,5,1] => 3
[6,4,2,5,1,3] => 3
[6,4,2,5,3,1] => 4
[6,4,3,1,2,5] => 3
[6,4,3,1,5,2] => 4
[6,4,3,2,1,5] => 4
[6,4,3,2,5,1] => 4
[6,4,3,5,1,2] => 3
[6,4,3,5,2,1] => 4
[6,4,5,1,2,3] => 2
[6,4,5,1,3,2] => 3
[6,4,5,2,1,3] => 3
[6,4,5,2,3,1] => 3
[6,4,5,3,1,2] => 3
[6,4,5,3,2,1] => 4
[6,5,1,2,3,4] => 2
[6,5,1,2,4,3] => 3
[6,5,1,3,2,4] => 3
[6,5,1,3,4,2] => 3
[6,5,1,4,2,3] => 3
[6,5,1,4,3,2] => 4
[6,5,2,1,3,4] => 3
[6,5,2,1,4,3] => 4
[6,5,2,3,1,4] => 3
[6,5,2,3,4,1] => 3
[6,5,2,4,1,3] => 3
[6,5,2,4,3,1] => 4
[6,5,3,1,2,4] => 3
[6,5,3,1,4,2] => 4
[6,5,3,2,1,4] => 4
[6,5,3,2,4,1] => 4
[6,5,3,4,1,2] => 3
[6,5,3,4,2,1] => 4
[6,5,4,1,2,3] => 3
[6,5,4,1,3,2] => 4
[6,5,4,2,1,3] => 4
[6,5,4,2,3,1] => 4
[6,5,4,3,1,2] => 4
[6,5,4,3,2,1] => 5

-----------------------------------------------------------------------------
Created: Oct 11, 2011 at 19:06 by Christian Stump

-----------------------------------------------------------------------------
Last Updated: May 10, 2019 at 17:11 by Henning  Ulfarsson