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*       Copyright (C) 2019 The FindStatCrew <info@findstat.org>             *
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Statistic identifier: St000770

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Collection: Integer partitions

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Description: The major index of an integer partition when read from bottom to top.

This is the sum of the positions of the corners of the shape of an integer partition when reading from bottom to top.

For example, the partition $\lambda = (8,6,6,4,3,3)$ has corners at positions 3,6,9, and 13, giving a major index of 31.

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References: 

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Code:
def statistic(L):
    L = list(L) + [0]
    return sum( len(L)-i-2+L[i] for i in range(len(L)-1) if L[i] > L[i+1] )


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Statistic values:

[2]                       => 2
[1,1]                     => 1
[3]                       => 3
[2,1]                     => 4
[1,1,1]                   => 1
[4]                       => 4
[3,1]                     => 5
[2,2]                     => 2
[2,1,1]                   => 5
[1,1,1,1]                 => 1
[5]                       => 5
[4,1]                     => 6
[3,2]                     => 6
[3,1,1]                   => 6
[2,2,1]                   => 4
[2,1,1,1]                 => 6
[1,1,1,1,1]               => 1
[6]                       => 6
[5,1]                     => 7
[4,2]                     => 7
[4,1,1]                   => 7
[3,3]                     => 3
[3,2,1]                   => 9
[3,1,1,1]                 => 7
[2,2,2]                   => 2
[2,2,1,1]                 => 5
[2,1,1,1,1]               => 7
[1,1,1,1,1,1]             => 1
[7]                       => 7
[6,1]                     => 8
[5,2]                     => 8
[5,1,1]                   => 8
[4,3]                     => 8
[4,2,1]                   => 10
[4,1,1,1]                 => 8
[3,3,1]                   => 5
[3,2,2]                   => 7
[3,2,1,1]                 => 11
[3,1,1,1,1]               => 8
[2,2,2,1]                 => 4
[2,2,1,1,1]               => 6
[2,1,1,1,1,1]             => 8
[1,1,1,1,1,1,1]           => 1
[8]                       => 8
[7,1]                     => 9
[6,2]                     => 9
[6,1,1]                   => 9
[5,3]                     => 9
[5,2,1]                   => 11
[5,1,1,1]                 => 9
[4,4]                     => 4
[4,3,1]                   => 11
[4,2,2]                   => 8
[4,2,1,1]                 => 12
[4,1,1,1,1]               => 9
[3,3,2]                   => 6
[3,3,1,1]                 => 6
[3,2,2,1]                 => 10
[3,2,1,1,1]               => 13
[3,1,1,1,1,1]             => 9
[2,2,2,2]                 => 2
[2,2,2,1,1]               => 5
[2,2,1,1,1,1]             => 7
[2,1,1,1,1,1,1]           => 9
[1,1,1,1,1,1,1,1]         => 1
[9]                       => 9
[8,1]                     => 10
[7,2]                     => 10
[7,1,1]                   => 10
[6,3]                     => 10
[6,2,1]                   => 12
[6,1,1,1]                 => 10
[5,4]                     => 10
[5,3,1]                   => 12
[5,2,2]                   => 9
[5,2,1,1]                 => 13
[5,1,1,1,1]               => 10
[4,4,1]                   => 6
[4,3,2]                   => 12
[4,3,1,1]                 => 13
[4,2,2,1]                 => 11
[4,2,1,1,1]               => 14
[4,1,1,1,1,1]             => 10
[3,3,3]                   => 3
[3,3,2,1]                 => 9
[3,3,1,1,1]               => 7
[3,2,2,2]                 => 8
[3,2,2,1,1]               => 12
[3,2,1,1,1,1]             => 15
[3,1,1,1,1,1,1]           => 10
[2,2,2,2,1]               => 4
[2,2,2,1,1,1]             => 6
[2,2,1,1,1,1,1]           => 8
[2,1,1,1,1,1,1,1]         => 10
[1,1,1,1,1,1,1,1,1]       => 1
[10]                      => 10
[9,1]                     => 11
[8,2]                     => 11
[8,1,1]                   => 11
[7,3]                     => 11
[7,2,1]                   => 13
[7,1,1,1]                 => 11
[6,4]                     => 11
[6,3,1]                   => 13
[6,2,2]                   => 10
[6,2,1,1]                 => 14
[6,1,1,1,1]               => 11
[5,5]                     => 5
[5,4,1]                   => 13
[5,3,2]                   => 13
[5,3,1,1]                 => 14
[5,2,2,1]                 => 12
[5,2,1,1,1]               => 15
[5,1,1,1,1,1]             => 11
[4,4,2]                   => 7
[4,4,1,1]                 => 7
[4,3,3]                   => 9
[4,3,2,1]                 => 16
[4,3,1,1,1]               => 15
[4,2,2,2]                 => 9
[4,2,2,1,1]               => 13
[4,2,1,1,1,1]             => 16
[4,1,1,1,1,1,1]           => 11
[3,3,3,1]                 => 5
[3,3,2,2]                 => 7
[3,3,2,1,1]               => 11
[3,3,1,1,1,1]             => 8
[3,2,2,2,1]               => 11
[3,2,2,1,1,1]             => 14
[3,2,1,1,1,1,1]           => 17
[3,1,1,1,1,1,1,1]         => 11
[2,2,2,2,2]               => 2
[2,2,2,2,1,1]             => 5
[2,2,2,1,1,1,1]           => 7
[2,2,1,1,1,1,1,1]         => 9
[2,1,1,1,1,1,1,1,1]       => 11
[1,1,1,1,1,1,1,1,1,1]     => 1
[11]                      => 11
[10,1]                    => 12
[9,2]                     => 12
[9,1,1]                   => 12
[8,3]                     => 12
[8,2,1]                   => 14
[8,1,1,1]                 => 12
[7,4]                     => 12
[7,3,1]                   => 14
[7,2,2]                   => 11
[7,2,1,1]                 => 15
[7,1,1,1,1]               => 12
[6,5]                     => 12
[6,4,1]                   => 14
[6,3,2]                   => 14
[6,3,1,1]                 => 15
[6,2,2,1]                 => 13
[6,2,1,1,1]               => 16
[6,1,1,1,1,1]             => 12
[5,5,1]                   => 7
[5,4,2]                   => 14
[5,4,1,1]                 => 15
[5,3,3]                   => 10
[5,3,2,1]                 => 17
[5,3,1,1,1]               => 16
[5,2,2,2]                 => 10
[5,2,2,1,1]               => 14
[5,2,1,1,1,1]             => 17
[5,1,1,1,1,1,1]           => 12
[4,4,3]                   => 8
[4,4,2,1]                 => 10
[4,4,1,1,1]               => 8
[4,3,3,1]                 => 12
[4,3,2,2]                 => 14
[4,3,2,1,1]               => 19
[4,3,1,1,1,1]             => 17
[4,2,2,2,1]               => 12
[4,2,2,1,1,1]             => 15
[4,2,1,1,1,1,1]           => 18
[4,1,1,1,1,1,1,1]         => 12
[3,3,3,2]                 => 6
[3,3,3,1,1]               => 6
[3,3,2,2,1]               => 10
[3,3,2,1,1,1]             => 13
[3,3,1,1,1,1,1]           => 9
[3,2,2,2,2]               => 9
[3,2,2,2,1,1]             => 13
[3,2,2,1,1,1,1]           => 16
[3,2,1,1,1,1,1,1]         => 19
[3,1,1,1,1,1,1,1,1]       => 12
[2,2,2,2,2,1]             => 4
[2,2,2,2,1,1,1]           => 6
[2,2,2,1,1,1,1,1]         => 8
[2,2,1,1,1,1,1,1,1]       => 10
[2,1,1,1,1,1,1,1,1,1]     => 12
[1,1,1,1,1,1,1,1,1,1,1]   => 1
[12]                      => 12
[11,1]                    => 13
[10,2]                    => 13
[10,1,1]                  => 13
[9,3]                     => 13
[9,2,1]                   => 15
[9,1,1,1]                 => 13
[8,4]                     => 13
[8,3,1]                   => 15
[8,2,2]                   => 12
[8,2,1,1]                 => 16
[8,1,1,1,1]               => 13
[7,5]                     => 13
[7,4,1]                   => 15
[7,3,2]                   => 15
[7,3,1,1]                 => 16
[7,2,2,1]                 => 14
[7,2,1,1,1]               => 17
[7,1,1,1,1,1]             => 13
[6,6]                     => 6
[6,5,1]                   => 15
[6,4,2]                   => 15
[6,4,1,1]                 => 16
[6,3,3]                   => 11
[6,3,2,1]                 => 18
[6,3,1,1,1]               => 17
[6,2,2,2]                 => 11
[6,2,2,1,1]               => 15
[6,2,1,1,1,1]             => 18
[6,1,1,1,1,1,1]           => 13
[5,5,2]                   => 8
[5,5,1,1]                 => 8
[5,4,3]                   => 15
[5,4,2,1]                 => 18
[5,4,1,1,1]               => 17
[5,3,3,1]                 => 13
[5,3,2,2]                 => 15
[5,3,2,1,1]               => 20
[5,3,1,1,1,1]             => 18
[5,2,2,2,1]               => 13
[5,2,2,1,1,1]             => 16
[5,2,1,1,1,1,1]           => 19
[5,1,1,1,1,1,1,1]         => 13
[4,4,4]                   => 4
[4,4,3,1]                 => 11
[4,4,2,2]                 => 8
[4,4,2,1,1]               => 12
[4,4,1,1,1,1]             => 9
[4,3,3,2]                 => 13
[4,3,3,1,1]               => 14
[4,3,2,2,1]               => 18
[4,3,2,1,1,1]             => 22
[4,3,1,1,1,1,1]           => 19
[4,2,2,2,2]               => 10
[4,2,2,2,1,1]             => 14
[4,2,2,1,1,1,1]           => 17
[4,2,1,1,1,1,1,1]         => 20
[4,1,1,1,1,1,1,1,1]       => 13
[3,3,3,3]                 => 3
[3,3,3,2,1]               => 9
[3,3,3,1,1,1]             => 7
[3,3,2,2,2]               => 8
[3,3,2,2,1,1]             => 12
[3,3,2,1,1,1,1]           => 15
[3,3,1,1,1,1,1,1]         => 10
[3,2,2,2,2,1]             => 12
[3,2,2,2,1,1,1]           => 15
[3,2,2,1,1,1,1,1]         => 18
[3,2,1,1,1,1,1,1,1]       => 21
[3,1,1,1,1,1,1,1,1,1]     => 13
[2,2,2,2,2,2]             => 2
[2,2,2,2,2,1,1]           => 5
[2,2,2,2,1,1,1,1]         => 7
[2,2,2,1,1,1,1,1,1]       => 9
[2,2,1,1,1,1,1,1,1,1]     => 11
[2,1,1,1,1,1,1,1,1,1,1]   => 13
[1,1,1,1,1,1,1,1,1,1,1,1] => 1

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Created: Apr 10, 2017 at 15:37 by Christian Stump

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Last Updated: Apr 10, 2017 at 15:37 by Christian Stump