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*       Copyright (C) 2019 The FindStatCrew <info@findstat.org>             *
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Statistic identifier: St000867

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Collection: Integer partitions

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Description: The sum of the hook lengths in the first row of an integer partition.

For a cell in the Ferrers diagram of a partition, the hook length is given by the number of boxes to its right plus the number of boxes below plus one. This statistic is the sum of the hook lengths of the first row of a partition.

Put differently, for a partition of size $n$ with first parth $\lambda_1$, this is $\binom{\lambda_1}{2} + n$.

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References: 

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Code:
def statistic(L):
    return L.size() + binomial(L[0], 2)


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Statistic values:

[]                        => 0
[1]                       => 1
[2]                       => 3
[1,1]                     => 2
[3]                       => 6
[2,1]                     => 4
[1,1,1]                   => 3
[4]                       => 10
[3,1]                     => 7
[2,2]                     => 5
[2,1,1]                   => 5
[1,1,1,1]                 => 4
[5]                       => 15
[4,1]                     => 11
[3,2]                     => 8
[3,1,1]                   => 8
[2,2,1]                   => 6
[2,1,1,1]                 => 6
[1,1,1,1,1]               => 5
[6]                       => 21
[5,1]                     => 16
[4,2]                     => 12
[4,1,1]                   => 12
[3,3]                     => 9
[3,2,1]                   => 9
[3,1,1,1]                 => 9
[2,2,2]                   => 7
[2,2,1,1]                 => 7
[2,1,1,1,1]               => 7
[1,1,1,1,1,1]             => 6
[7]                       => 28
[6,1]                     => 22
[5,2]                     => 17
[5,1,1]                   => 17
[4,3]                     => 13
[4,2,1]                   => 13
[4,1,1,1]                 => 13
[3,3,1]                   => 10
[3,2,2]                   => 10
[3,2,1,1]                 => 10
[3,1,1,1,1]               => 10
[2,2,2,1]                 => 8
[2,2,1,1,1]               => 8
[2,1,1,1,1,1]             => 8
[1,1,1,1,1,1,1]           => 7
[8]                       => 36
[7,1]                     => 29
[6,2]                     => 23
[6,1,1]                   => 23
[5,3]                     => 18
[5,2,1]                   => 18
[5,1,1,1]                 => 18
[4,4]                     => 14
[4,3,1]                   => 14
[4,2,2]                   => 14
[4,2,1,1]                 => 14
[4,1,1,1,1]               => 14
[3,3,2]                   => 11
[3,3,1,1]                 => 11
[3,2,2,1]                 => 11
[3,2,1,1,1]               => 11
[3,1,1,1,1,1]             => 11
[2,2,2,2]                 => 9
[2,2,2,1,1]               => 9
[2,2,1,1,1,1]             => 9
[2,1,1,1,1,1,1]           => 9
[1,1,1,1,1,1,1,1]         => 8
[9]                       => 45
[8,1]                     => 37
[7,2]                     => 30
[7,1,1]                   => 30
[6,3]                     => 24
[6,2,1]                   => 24
[6,1,1,1]                 => 24
[5,4]                     => 19
[5,3,1]                   => 19
[5,2,2]                   => 19
[5,2,1,1]                 => 19
[5,1,1,1,1]               => 19
[4,4,1]                   => 15
[4,3,2]                   => 15
[4,3,1,1]                 => 15
[4,2,2,1]                 => 15
[4,2,1,1,1]               => 15
[4,1,1,1,1,1]             => 15
[3,3,3]                   => 12
[3,3,2,1]                 => 12
[3,3,1,1,1]               => 12
[3,2,2,2]                 => 12
[3,2,2,1,1]               => 12
[3,2,1,1,1,1]             => 12
[3,1,1,1,1,1,1]           => 12
[2,2,2,2,1]               => 10
[2,2,2,1,1,1]             => 10
[2,2,1,1,1,1,1]           => 10
[2,1,1,1,1,1,1,1]         => 10
[1,1,1,1,1,1,1,1,1]       => 9
[10]                      => 55
[9,1]                     => 46
[8,2]                     => 38
[8,1,1]                   => 38
[7,3]                     => 31
[7,2,1]                   => 31
[7,1,1,1]                 => 31
[6,4]                     => 25
[6,3,1]                   => 25
[6,2,2]                   => 25
[6,2,1,1]                 => 25
[6,1,1,1,1]               => 25
[5,5]                     => 20
[5,4,1]                   => 20
[5,3,2]                   => 20
[5,3,1,1]                 => 20
[5,2,2,1]                 => 20
[5,2,1,1,1]               => 20
[5,1,1,1,1,1]             => 20
[4,4,2]                   => 16
[4,4,1,1]                 => 16
[4,3,3]                   => 16
[4,3,2,1]                 => 16
[4,3,1,1,1]               => 16
[4,2,2,2]                 => 16
[4,2,2,1,1]               => 16
[4,2,1,1,1,1]             => 16
[4,1,1,1,1,1,1]           => 16
[3,3,3,1]                 => 13
[3,3,2,2]                 => 13
[3,3,2,1,1]               => 13
[3,3,1,1,1,1]             => 13
[3,2,2,2,1]               => 13
[3,2,2,1,1,1]             => 13
[3,2,1,1,1,1,1]           => 13
[3,1,1,1,1,1,1,1]         => 13
[2,2,2,2,2]               => 11
[2,2,2,2,1,1]             => 11
[2,2,2,1,1,1,1]           => 11
[2,2,1,1,1,1,1,1]         => 11
[2,1,1,1,1,1,1,1,1]       => 11
[1,1,1,1,1,1,1,1,1,1]     => 10
[11]                      => 66
[10,1]                    => 56
[9,2]                     => 47
[9,1,1]                   => 47
[8,3]                     => 39
[8,2,1]                   => 39
[8,1,1,1]                 => 39
[7,4]                     => 32
[7,3,1]                   => 32
[7,2,2]                   => 32
[7,2,1,1]                 => 32
[7,1,1,1,1]               => 32
[6,5]                     => 26
[6,4,1]                   => 26
[6,3,2]                   => 26
[6,3,1,1]                 => 26
[6,2,2,1]                 => 26
[6,2,1,1,1]               => 26
[6,1,1,1,1,1]             => 26
[5,5,1]                   => 21
[5,4,2]                   => 21
[5,4,1,1]                 => 21
[5,3,3]                   => 21
[5,3,2,1]                 => 21
[5,3,1,1,1]               => 21
[5,2,2,2]                 => 21
[5,2,2,1,1]               => 21
[5,2,1,1,1,1]             => 21
[5,1,1,1,1,1,1]           => 21
[4,4,3]                   => 17
[4,4,2,1]                 => 17
[4,4,1,1,1]               => 17
[4,3,3,1]                 => 17
[4,3,2,2]                 => 17
[4,3,2,1,1]               => 17
[4,3,1,1,1,1]             => 17
[4,2,2,2,1]               => 17
[4,2,2,1,1,1]             => 17
[4,2,1,1,1,1,1]           => 17
[4,1,1,1,1,1,1,1]         => 17
[3,3,3,2]                 => 14
[3,3,3,1,1]               => 14
[3,3,2,2,1]               => 14
[3,3,2,1,1,1]             => 14
[3,3,1,1,1,1,1]           => 14
[3,2,2,2,2]               => 14
[3,2,2,2,1,1]             => 14
[3,2,2,1,1,1,1]           => 14
[3,2,1,1,1,1,1,1]         => 14
[3,1,1,1,1,1,1,1,1]       => 14
[2,2,2,2,2,1]             => 12
[2,2,2,2,1,1,1]           => 12
[2,2,2,1,1,1,1,1]         => 12
[2,2,1,1,1,1,1,1,1]       => 12
[2,1,1,1,1,1,1,1,1,1]     => 12
[1,1,1,1,1,1,1,1,1,1,1]   => 11
[12]                      => 78
[11,1]                    => 67
[10,2]                    => 57
[10,1,1]                  => 57
[9,3]                     => 48
[9,2,1]                   => 48
[9,1,1,1]                 => 48
[8,4]                     => 40
[8,3,1]                   => 40
[8,2,2]                   => 40
[8,2,1,1]                 => 40
[8,1,1,1,1]               => 40
[7,5]                     => 33
[7,4,1]                   => 33
[7,3,2]                   => 33
[7,3,1,1]                 => 33
[7,2,2,1]                 => 33
[7,2,1,1,1]               => 33
[7,1,1,1,1,1]             => 33
[6,6]                     => 27
[6,5,1]                   => 27
[6,4,2]                   => 27
[6,4,1,1]                 => 27
[6,3,3]                   => 27
[6,3,2,1]                 => 27
[6,3,1,1,1]               => 27
[6,2,2,2]                 => 27
[6,2,2,1,1]               => 27
[6,2,1,1,1,1]             => 27
[6,1,1,1,1,1,1]           => 27
[5,5,2]                   => 22
[5,5,1,1]                 => 22
[5,4,3]                   => 22
[5,4,2,1]                 => 22
[5,4,1,1,1]               => 22
[5,3,3,1]                 => 22
[5,3,2,2]                 => 22
[5,3,2,1,1]               => 22
[5,3,1,1,1,1]             => 22
[5,2,2,2,1]               => 22
[5,2,2,1,1,1]             => 22
[5,2,1,1,1,1,1]           => 22
[5,1,1,1,1,1,1,1]         => 22
[4,4,4]                   => 18
[4,4,3,1]                 => 18
[4,4,2,2]                 => 18
[4,4,2,1,1]               => 18
[4,4,1,1,1,1]             => 18
[4,3,3,2]                 => 18
[4,3,3,1,1]               => 18
[4,3,2,2,1]               => 18
[4,3,2,1,1,1]             => 18
[4,3,1,1,1,1,1]           => 18
[4,2,2,2,2]               => 18
[4,2,2,2,1,1]             => 18
[4,2,2,1,1,1,1]           => 18
[4,2,1,1,1,1,1,1]         => 18
[4,1,1,1,1,1,1,1,1]       => 18
[3,3,3,3]                 => 15
[3,3,3,2,1]               => 15
[3,3,3,1,1,1]             => 15
[3,3,2,2,2]               => 15
[3,3,2,2,1,1]             => 15
[3,3,2,1,1,1,1]           => 15
[3,3,1,1,1,1,1,1]         => 15
[3,2,2,2,2,1]             => 15
[3,2,2,2,1,1,1]           => 15
[3,2,2,1,1,1,1,1]         => 15
[3,2,1,1,1,1,1,1,1]       => 15
[3,1,1,1,1,1,1,1,1,1]     => 15
[2,2,2,2,2,2]             => 13
[2,2,2,2,2,1,1]           => 13
[2,2,2,2,1,1,1,1]         => 13
[2,2,2,1,1,1,1,1,1]       => 13
[2,2,1,1,1,1,1,1,1,1]     => 13
[2,1,1,1,1,1,1,1,1,1,1]   => 13
[1,1,1,1,1,1,1,1,1,1,1,1] => 12
[5,4,3,1]                 => 23
[5,4,2,2]                 => 23
[5,4,2,1,1]               => 23
[5,3,3,2]                 => 23
[5,3,3,1,1]               => 23
[5,3,2,2,1]               => 23
[4,4,3,2]                 => 19
[4,4,3,1,1]               => 19
[4,4,2,2,1]               => 19
[4,3,3,2,1]               => 19
[5,4,3,2]                 => 24
[5,4,3,1,1]               => 24
[5,4,2,2,1]               => 24
[5,3,3,2,1]               => 24
[4,4,3,2,1]               => 20
[5,4,3,2,1]               => 25

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Created: Jun 27, 2017 at 09:08 by Christian Stump

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Last Updated: Jun 19, 2020 at 13:57 by Martin Rubey