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Statistic identifier: St000618

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Collection: Integer partitions

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Description: The number of self-evacuating tableaux of given shape.

This is the same as the number of standard domino tableaux of the given shape.

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References: [1]   Stembridge, J. R. Canonical bases and self-evacuating tableaux [[MathSciNet:1387685]]

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Code:
def statistic_alt(la):
    chi = SymmetricGroupRepresentation(la)
    r = abs(ZZ(chi.to_character()(Permutation(range(la.size(),0,-1)))))
    assert r==statistic(la)
    return r

def statistic(la):
    n = la.size()
    la = la + [0]*(n-len(la))

    E_la = sorted([la[j] + n-j-1 for j in range(n) if is_even(la[j] + n-j-1)], reverse=True)
    rE = len(E_la)
    la_e = [ZZ(E_la[i]/2-rE+i+1) for i in range(rE)]
    
    O_la = sorted([la[j] + n-j-2 for j in range(n) if is_even(la[j] +n-j-2)], reverse=True)
    rO = len(O_la)
    la_o = [ZZ(O_la[i]/2-rO+i+1) for i in range(rO)]

    if abs(rE - rO)<=1:
        return (binomial(n//2, sum(la_e))*
                StandardTableaux(la_e).cardinality()*
                StandardTableaux(la_o).cardinality())
    else:
        return 0


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Statistic values:

[1]                       => 1
[2]                       => 1
[1,1]                     => 1
[3]                       => 1
[2,1]                     => 0
[1,1,1]                   => 1
[4]                       => 1
[3,1]                     => 1
[2,2]                     => 2
[2,1,1]                   => 1
[1,1,1,1]                 => 1
[5]                       => 1
[4,1]                     => 0
[3,2]                     => 1
[3,1,1]                   => 2
[2,2,1]                   => 1
[2,1,1,1]                 => 0
[1,1,1,1,1]               => 1
[6]                       => 1
[5,1]                     => 1
[4,2]                     => 3
[4,1,1]                   => 2
[3,3]                     => 3
[3,2,1]                   => 0
[3,1,1,1]                 => 2
[2,2,2]                   => 3
[2,2,1,1]                 => 3
[2,1,1,1,1]               => 1
[1,1,1,1,1,1]             => 1
[7]                       => 1
[6,1]                     => 0
[5,2]                     => 2
[5,1,1]                   => 3
[4,3]                     => 0
[4,2,1]                   => 1
[4,1,1,1]                 => 0
[3,3,1]                   => 3
[3,2,2]                   => 3
[3,2,1,1]                 => 1
[3,1,1,1,1]               => 3
[2,2,2,1]                 => 0
[2,2,1,1,1]               => 2
[2,1,1,1,1,1]             => 0
[1,1,1,1,1,1,1]           => 1
[8]                       => 1
[7,1]                     => 1
[6,2]                     => 4
[6,1,1]                   => 3
[5,3]                     => 4
[5,2,1]                   => 0
[5,1,1,1]                 => 3
[4,4]                     => 6
[4,3,1]                   => 2
[4,2,2]                   => 8
[4,2,1,1]                 => 6
[4,1,1,1,1]               => 3
[3,3,2]                   => 6
[3,3,1,1]                 => 8
[3,2,2,1]                 => 2
[3,2,1,1,1]               => 0
[3,1,1,1,1,1]             => 3
[2,2,2,2]                 => 6
[2,2,2,1,1]               => 4
[2,2,1,1,1,1]             => 4
[2,1,1,1,1,1,1]           => 1
[1,1,1,1,1,1,1,1]         => 1
[9]                       => 1
[8,1]                     => 0
[7,2]                     => 3
[7,1,1]                   => 4
[6,3]                     => 0
[6,2,1]                   => 1
[6,1,1,1]                 => 0
[5,4]                     => 2
[5,3,1]                   => 6
[5,2,2]                   => 8
[5,2,1,1]                 => 3
[5,1,1,1,1]               => 6
[4,4,1]                   => 4
[4,3,2]                   => 0
[4,3,1,1]                 => 0
[4,2,2,1]                 => 0
[4,2,1,1,1]               => 3
[4,1,1,1,1,1]             => 0
[3,3,3]                   => 6
[3,3,2,1]                 => 0
[3,3,1,1,1]               => 8
[3,2,2,2]                 => 4
[3,2,2,1,1]               => 6
[3,2,1,1,1,1]             => 1
[3,1,1,1,1,1,1]           => 4
[2,2,2,2,1]               => 2
[2,2,2,1,1,1]             => 0
[2,2,1,1,1,1,1]           => 3
[2,1,1,1,1,1,1,1]         => 0
[1,1,1,1,1,1,1,1,1]       => 1
[10]                      => 1
[9,1]                     => 1
[8,2]                     => 5
[8,1,1]                   => 4
[7,3]                     => 5
[7,2,1]                   => 0
[7,1,1,1]                 => 4
[6,4]                     => 10
[6,3,1]                   => 5
[6,2,2]                   => 15
[6,2,1,1]                 => 10
[6,1,1,1,1]               => 6
[5,5]                     => 10
[5,4,1]                   => 0
[5,3,2]                   => 10
[5,3,1,1]                 => 15
[5,2,2,1]                 => 5
[5,2,1,1,1]               => 0
[5,1,1,1,1,1]             => 6
[4,4,2]                   => 20
[4,4,1,1]                 => 20
[4,3,3]                   => 10
[4,3,2,1]                 => 0
[4,3,1,1,1]               => 5
[4,2,2,2]                 => 20
[4,2,2,1,1]               => 15
[4,2,1,1,1,1]             => 10
[4,1,1,1,1,1,1]           => 4
[3,3,3,1]                 => 10
[3,3,2,2]                 => 20
[3,3,2,1,1]               => 10
[3,3,1,1,1,1]             => 15
[3,2,2,2,1]               => 0
[3,2,2,1,1,1]             => 5
[3,2,1,1,1,1,1]           => 0
[3,1,1,1,1,1,1,1]         => 4
[2,2,2,2,2]               => 10
[2,2,2,2,1,1]             => 10
[2,2,2,1,1,1,1]           => 5
[2,2,1,1,1,1,1,1]         => 5
[2,1,1,1,1,1,1,1,1]       => 1
[1,1,1,1,1,1,1,1,1,1]     => 1
[11]                      => 1
[10,1]                    => 0
[9,2]                     => 4
[9,1,1]                   => 5
[8,3]                     => 0
[8,2,1]                   => 1
[8,1,1,1]                 => 0
[7,4]                     => 5
[7,3,1]                   => 10
[7,2,2]                   => 15
[7,2,1,1]                 => 6
[7,1,1,1,1]               => 10
[6,5]                     => 0
[6,4,1]                   => 5
[6,3,2]                   => 0
[6,3,1,1]                 => 0
[6,2,2,1]                 => 0
[6,2,1,1,1]               => 4
[6,1,1,1,1,1]             => 0
[5,5,1]                   => 10
[5,4,2]                   => 10
[5,4,1,1]                 => 5
[5,3,3]                   => 20
[5,3,2,1]                 => 0
[5,3,1,1,1]               => 20
[5,2,2,2]                 => 15
[5,2,2,1,1]               => 20
[5,2,1,1,1,1]             => 4
[5,1,1,1,1,1,1]           => 10
[4,4,3]                   => 10
[4,4,2,1]                 => 0
[4,4,1,1,1]               => 15
[4,3,3,1]                 => 0
[4,3,2,2]                 => 0
[4,3,2,1,1]               => 0
[4,3,1,1,1,1]             => 0
[4,2,2,2,1]               => 5
[4,2,2,1,1,1]             => 0
[4,2,1,1,1,1,1]           => 6
[4,1,1,1,1,1,1,1]         => 0
[3,3,3,2]                 => 10
[3,3,3,1,1]               => 20
[3,3,2,2,1]               => 10
[3,3,2,1,1,1]             => 0
[3,3,1,1,1,1,1]           => 15
[3,2,2,2,2]               => 10
[3,2,2,2,1,1]             => 5
[3,2,2,1,1,1,1]           => 10
[3,2,1,1,1,1,1,1]         => 1
[3,1,1,1,1,1,1,1,1]       => 5
[2,2,2,2,2,1]             => 0
[2,2,2,2,1,1,1]           => 5
[2,2,2,1,1,1,1,1]         => 0
[2,2,1,1,1,1,1,1,1]       => 4
[2,1,1,1,1,1,1,1,1,1]     => 0
[1,1,1,1,1,1,1,1,1,1,1]   => 1
[12]                      => 1
[11,1]                    => 1
[10,2]                    => 6
[10,1,1]                  => 5
[9,3]                     => 6
[9,2,1]                   => 0
[9,1,1,1]                 => 5
[8,4]                     => 15
[8,3,1]                   => 9
[8,2,2]                   => 24
[8,2,1,1]                 => 15
[8,1,1,1,1]               => 10
[7,5]                     => 15
[7,4,1]                   => 0
[7,3,2]                   => 15
[7,3,1,1]                 => 24
[7,2,2,1]                 => 9
[7,2,1,1,1]               => 0
[7,1,1,1,1,1]             => 10
[6,6]                     => 20
[6,5,1]                   => 5
[6,4,2]                   => 45
[6,4,1,1]                 => 40
[6,3,3]                   => 30
[6,3,2,1]                 => 0
[6,3,1,1,1]               => 16
[6,2,2,2]                 => 45
[6,2,2,1,1]               => 36
[6,2,1,1,1,1]             => 20
[6,1,1,1,1,1,1]           => 10
[5,5,2]                   => 40
[5,5,1,1]                 => 45
[5,4,3]                   => 0
[5,4,2,1]                 => 5
[5,4,1,1,1]               => 0
[5,3,3,1]                 => 30
[5,3,2,2]                 => 45
[5,3,2,1,1]               => 20
[5,3,1,1,1,1]             => 36
[5,2,2,2,1]               => 0
[5,2,2,1,1,1]             => 16
[5,2,1,1,1,1,1]           => 0
[5,1,1,1,1,1,1,1]         => 10
[4,4,4]                   => 30
[4,4,3,1]                 => 30
[4,4,2,2]                 => 80
[4,4,2,1,1]               => 45
[4,4,1,1,1,1]             => 45
[4,3,3,2]                 => 30
[4,3,3,1,1]               => 30
[4,3,2,2,1]               => 5
[4,3,2,1,1,1]             => 0
[4,3,1,1,1,1,1]           => 9
[4,2,2,2,2]               => 45
[4,2,2,2,1,1]             => 40
[4,2,2,1,1,1,1]           => 24
[4,2,1,1,1,1,1,1]         => 15
[4,1,1,1,1,1,1,1,1]       => 5
[3,3,3,3]                 => 30
[3,3,3,2,1]               => 0
[3,3,3,1,1,1]             => 30
[3,3,2,2,2]               => 40
[3,3,2,2,1,1]             => 45
[3,3,2,1,1,1,1]           => 15
[3,3,1,1,1,1,1,1]         => 24
[3,2,2,2,2,1]             => 5
[3,2,2,2,1,1,1]           => 0
[3,2,2,1,1,1,1,1]         => 9
[3,2,1,1,1,1,1,1,1]       => 0
[3,1,1,1,1,1,1,1,1,1]     => 5
[2,2,2,2,2,2]             => 20
[2,2,2,2,2,1,1]           => 15
[2,2,2,2,1,1,1,1]         => 15
[2,2,2,1,1,1,1,1,1]       => 6
[2,2,1,1,1,1,1,1,1,1]     => 6
[2,1,1,1,1,1,1,1,1,1,1]   => 1
[1,1,1,1,1,1,1,1,1,1,1,1] => 1

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Created: Sep 26, 2016 at 23:00 by Martin Rubey

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Last Updated: Sep 26, 2016 at 23:00 by Martin Rubey