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Statistic identifier: St000997

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Collection: Integer partitions

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Description: The even-odd crank of an integer partition.

This is the largest even part minus the number of odd parts.

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References: [1]   Chern, S. On partitions with even parts below odd parts [[arXiv:1710.08507]]

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Code:
def largest_even_part(L):
    L += [0]
    for a in L:
        if is_even(a):
            return a

def statistic(L):
    return largest_even_part(L) - sum( 1 for a in L if is_odd(a) )


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Statistic values:

[2]                       => 2
[1,1]                     => -2
[3]                       => -1
[2,1]                     => 1
[1,1,1]                   => -3
[4]                       => 4
[3,1]                     => -2
[2,2]                     => 2
[2,1,1]                   => 0
[1,1,1,1]                 => -4
[5]                       => -1
[4,1]                     => 3
[3,2]                     => 1
[3,1,1]                   => -3
[2,2,1]                   => 1
[2,1,1,1]                 => -1
[1,1,1,1,1]               => -5
[6]                       => 6
[5,1]                     => -2
[4,2]                     => 4
[4,1,1]                   => 2
[3,3]                     => -2
[3,2,1]                   => 0
[3,1,1,1]                 => -4
[2,2,2]                   => 2
[2,2,1,1]                 => 0
[2,1,1,1,1]               => -2
[1,1,1,1,1,1]             => -6
[7]                       => -1
[6,1]                     => 5
[5,2]                     => 1
[5,1,1]                   => -3
[4,3]                     => 3
[4,2,1]                   => 3
[4,1,1,1]                 => 1
[3,3,1]                   => -3
[3,2,2]                   => 1
[3,2,1,1]                 => -1
[3,1,1,1,1]               => -5
[2,2,2,1]                 => 1
[2,2,1,1,1]               => -1
[2,1,1,1,1,1]             => -3
[1,1,1,1,1,1,1]           => -7
[8]                       => 8
[7,1]                     => -2
[6,2]                     => 6
[6,1,1]                   => 4
[5,3]                     => -2
[5,2,1]                   => 0
[5,1,1,1]                 => -4
[4,4]                     => 4
[4,3,1]                   => 2
[4,2,2]                   => 4
[4,2,1,1]                 => 2
[4,1,1,1,1]               => 0
[3,3,2]                   => 0
[3,3,1,1]                 => -4
[3,2,2,1]                 => 0
[3,2,1,1,1]               => -2
[3,1,1,1,1,1]             => -6
[2,2,2,2]                 => 2
[2,2,2,1,1]               => 0
[2,2,1,1,1,1]             => -2
[2,1,1,1,1,1,1]           => -4
[1,1,1,1,1,1,1,1]         => -8
[9]                       => -1
[8,1]                     => 7
[7,2]                     => 1
[7,1,1]                   => -3
[6,3]                     => 5
[6,2,1]                   => 5
[6,1,1,1]                 => 3
[5,4]                     => 3
[5,3,1]                   => -3
[5,2,2]                   => 1
[5,2,1,1]                 => -1
[5,1,1,1,1]               => -5
[4,4,1]                   => 3
[4,3,2]                   => 3
[4,3,1,1]                 => 1
[4,2,2,1]                 => 3
[4,2,1,1,1]               => 1
[4,1,1,1,1,1]             => -1
[3,3,3]                   => -3
[3,3,2,1]                 => -1
[3,3,1,1,1]               => -5
[3,2,2,2]                 => 1
[3,2,2,1,1]               => -1
[3,2,1,1,1,1]             => -3
[3,1,1,1,1,1,1]           => -7
[2,2,2,2,1]               => 1
[2,2,2,1,1,1]             => -1
[2,2,1,1,1,1,1]           => -3
[2,1,1,1,1,1,1,1]         => -5
[1,1,1,1,1,1,1,1,1]       => -9
[10]                      => 10
[9,1]                     => -2
[8,2]                     => 8
[8,1,1]                   => 6
[7,3]                     => -2
[7,2,1]                   => 0
[7,1,1,1]                 => -4
[6,4]                     => 6
[6,3,1]                   => 4
[6,2,2]                   => 6
[6,2,1,1]                 => 4
[6,1,1,1,1]               => 2
[5,5]                     => -2
[5,4,1]                   => 2
[5,3,2]                   => 0
[5,3,1,1]                 => -4
[5,2,2,1]                 => 0
[5,2,1,1,1]               => -2
[5,1,1,1,1,1]             => -6
[4,4,2]                   => 4
[4,4,1,1]                 => 2
[4,3,3]                   => 2
[4,3,2,1]                 => 2
[4,3,1,1,1]               => 0
[4,2,2,2]                 => 4
[4,2,2,1,1]               => 2
[4,2,1,1,1,1]             => 0
[4,1,1,1,1,1,1]           => -2
[3,3,3,1]                 => -4
[3,3,2,2]                 => 0
[3,3,2,1,1]               => -2
[3,3,1,1,1,1]             => -6
[3,2,2,2,1]               => 0
[3,2,2,1,1,1]             => -2
[3,2,1,1,1,1,1]           => -4
[3,1,1,1,1,1,1,1]         => -8
[2,2,2,2,2]               => 2
[2,2,2,2,1,1]             => 0
[2,2,2,1,1,1,1]           => -2
[2,2,1,1,1,1,1,1]         => -4
[2,1,1,1,1,1,1,1,1]       => -6
[1,1,1,1,1,1,1,1,1,1]     => -10
[11]                      => -1
[10,1]                    => 9
[9,2]                     => 1
[9,1,1]                   => -3
[8,3]                     => 7
[8,2,1]                   => 7
[8,1,1,1]                 => 5
[7,4]                     => 3
[7,3,1]                   => -3
[7,2,2]                   => 1
[7,2,1,1]                 => -1
[7,1,1,1,1]               => -5
[6,5]                     => 5
[6,4,1]                   => 5
[6,3,2]                   => 5
[6,3,1,1]                 => 3
[6,2,2,1]                 => 5
[6,2,1,1,1]               => 3
[6,1,1,1,1,1]             => 1
[5,5,1]                   => -3
[5,4,2]                   => 3
[5,4,1,1]                 => 1
[5,3,3]                   => -3
[5,3,2,1]                 => -1
[5,3,1,1,1]               => -5
[5,2,2,2]                 => 1
[5,2,2,1,1]               => -1
[5,2,1,1,1,1]             => -3
[5,1,1,1,1,1,1]           => -7
[4,4,3]                   => 3
[4,4,2,1]                 => 3
[4,4,1,1,1]               => 1
[4,3,3,1]                 => 1
[4,3,2,2]                 => 3
[4,3,2,1,1]               => 1
[4,3,1,1,1,1]             => -1
[4,2,2,2,1]               => 3
[4,2,2,1,1,1]             => 1
[4,2,1,1,1,1,1]           => -1
[4,1,1,1,1,1,1,1]         => -3
[3,3,3,2]                 => -1
[3,3,3,1,1]               => -5
[3,3,2,2,1]               => -1
[3,3,2,1,1,1]             => -3
[3,3,1,1,1,1,1]           => -7
[3,2,2,2,2]               => 1
[3,2,2,2,1,1]             => -1
[3,2,2,1,1,1,1]           => -3
[3,2,1,1,1,1,1,1]         => -5
[3,1,1,1,1,1,1,1,1]       => -9
[2,2,2,2,2,1]             => 1
[2,2,2,2,1,1,1]           => -1
[2,2,2,1,1,1,1,1]         => -3
[2,2,1,1,1,1,1,1,1]       => -5
[2,1,1,1,1,1,1,1,1,1]     => -7
[1,1,1,1,1,1,1,1,1,1,1]   => -11
[12]                      => 12
[11,1]                    => -2
[10,2]                    => 10
[10,1,1]                  => 8
[9,3]                     => -2
[9,2,1]                   => 0
[9,1,1,1]                 => -4
[8,4]                     => 8
[8,3,1]                   => 6
[8,2,2]                   => 8
[8,2,1,1]                 => 6
[8,1,1,1,1]               => 4
[7,5]                     => -2
[7,4,1]                   => 2
[7,3,2]                   => 0
[7,3,1,1]                 => -4
[7,2,2,1]                 => 0
[7,2,1,1,1]               => -2
[7,1,1,1,1,1]             => -6
[6,6]                     => 6
[6,5,1]                   => 4
[6,4,2]                   => 6
[6,4,1,1]                 => 4
[6,3,3]                   => 4
[6,3,2,1]                 => 4
[6,3,1,1,1]               => 2
[6,2,2,2]                 => 6
[6,2,2,1,1]               => 4
[6,2,1,1,1,1]             => 2
[6,1,1,1,1,1,1]           => 0
[5,5,2]                   => 0
[5,5,1,1]                 => -4
[5,4,3]                   => 2
[5,4,2,1]                 => 2
[5,4,1,1,1]               => 0
[5,3,3,1]                 => -4
[5,3,2,2]                 => 0
[5,3,2,1,1]               => -2
[5,3,1,1,1,1]             => -6
[5,2,2,2,1]               => 0
[5,2,2,1,1,1]             => -2
[5,2,1,1,1,1,1]           => -4
[5,1,1,1,1,1,1,1]         => -8
[4,4,4]                   => 4
[4,4,3,1]                 => 2
[4,4,2,2]                 => 4
[4,4,2,1,1]               => 2
[4,4,1,1,1,1]             => 0
[4,3,3,2]                 => 2
[4,3,3,1,1]               => 0
[4,3,2,2,1]               => 2
[4,3,2,1,1,1]             => 0
[4,3,1,1,1,1,1]           => -2
[4,2,2,2,2]               => 4
[4,2,2,2,1,1]             => 2
[4,2,2,1,1,1,1]           => 0
[4,2,1,1,1,1,1,1]         => -2
[4,1,1,1,1,1,1,1,1]       => -4
[3,3,3,3]                 => -4
[3,3,3,2,1]               => -2
[3,3,3,1,1,1]             => -6
[3,3,2,2,2]               => 0
[3,3,2,2,1,1]             => -2
[3,3,2,1,1,1,1]           => -4
[3,3,1,1,1,1,1,1]         => -8
[3,2,2,2,2,1]             => 0
[3,2,2,2,1,1,1]           => -2
[3,2,2,1,1,1,1,1]         => -4
[3,2,1,1,1,1,1,1,1]       => -6
[3,1,1,1,1,1,1,1,1,1]     => -10
[2,2,2,2,2,2]             => 2
[2,2,2,2,2,1,1]           => 0
[2,2,2,2,1,1,1,1]         => -2
[2,2,2,1,1,1,1,1,1]       => -4
[2,2,1,1,1,1,1,1,1,1]     => -6
[2,1,1,1,1,1,1,1,1,1,1]   => -8
[1,1,1,1,1,1,1,1,1,1,1,1] => -12

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Created: Oct 25, 2017 at 21:43 by Christian Stump

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Last Updated: Oct 25, 2017 at 21:43 by Christian Stump