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Statistic identifier: St000343

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Collection: Graphs

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Description: The number of spanning subgraphs of a graph.

This is the number of subsets of the edge set of the graph, or the evaluation of the Tutte polynomial at $x=y=2$.

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References: 

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Code:
def statistic(x):
    return 2^x.num_edges()

def statistic_alternative(g):
    return g.tutte_polynomial().subs(x=Integer(2),y=Integer(2))


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

([],1)                                                                                          => 1
([],2)                                                                                          => 1
([(0,1)],2)                                                                                     => 2
([],3)                                                                                          => 1
([(1,2)],3)                                                                                     => 2
([(0,2),(1,2)],3)                                                                               => 4
([(0,1),(0,2),(1,2)],3)                                                                         => 8
([],4)                                                                                          => 1
([(2,3)],4)                                                                                     => 2
([(1,3),(2,3)],4)                                                                               => 4
([(0,3),(1,3),(2,3)],4)                                                                         => 8
([(0,3),(1,2)],4)                                                                               => 4
([(0,3),(1,2),(2,3)],4)                                                                         => 8
([(1,2),(1,3),(2,3)],4)                                                                         => 8
([(0,3),(1,2),(1,3),(2,3)],4)                                                                   => 16
([(0,2),(0,3),(1,2),(1,3)],4)                                                                   => 16
([(0,2),(0,3),(1,2),(1,3),(2,3)],4)                                                             => 32
([(0,1),(0,2),(0,3),(1,2),(1,3),(2,3)],4)                                                       => 64
([],5)                                                                                          => 1
([(3,4)],5)                                                                                     => 2
([(2,4),(3,4)],5)                                                                               => 4
([(1,4),(2,4),(3,4)],5)                                                                         => 8
([(0,4),(1,4),(2,4),(3,4)],5)                                                                   => 16
([(1,4),(2,3)],5)                                                                               => 4
([(1,4),(2,3),(3,4)],5)                                                                         => 8
([(0,1),(2,4),(3,4)],5)                                                                         => 8
([(2,3),(2,4),(3,4)],5)                                                                         => 8
([(0,4),(1,4),(2,3),(3,4)],5)                                                                   => 16
([(1,4),(2,3),(2,4),(3,4)],5)                                                                   => 16
([(0,4),(1,4),(2,3),(2,4),(3,4)],5)                                                             => 32
([(1,3),(1,4),(2,3),(2,4)],5)                                                                   => 16
([(0,4),(1,2),(1,3),(2,4),(3,4)],5)                                                             => 32
([(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                                             => 32
([(0,4),(1,3),(2,3),(2,4),(3,4)],5)                                                             => 32
([(0,4),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                                       => 64
([(0,3),(0,4),(1,3),(1,4),(2,3),(2,4)],5)                                                       => 64
([(0,3),(0,4),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                                 => 128
([(0,4),(1,3),(2,3),(2,4)],5)                                                                   => 16
([(0,1),(2,3),(2,4),(3,4)],5)                                                                   => 16
([(0,3),(1,2),(1,4),(2,4),(3,4)],5)                                                             => 32
([(0,3),(0,4),(1,2),(1,4),(2,4),(3,4)],5)                                                       => 64
([(0,3),(0,4),(1,2),(1,4),(2,3)],5)                                                             => 32
([(0,1),(0,4),(1,3),(2,3),(2,4),(3,4)],5)                                                       => 64
([(0,3),(0,4),(1,2),(1,4),(2,3),(2,4),(3,4)],5)                                                 => 128
([(0,4),(1,2),(1,3),(2,3),(2,4),(3,4)],5)                                                       => 64
([(1,2),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                                       => 64
([(0,4),(1,2),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                                 => 128
([(0,3),(0,4),(1,2),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                           => 256
([(0,3),(0,4),(1,2),(1,3),(1,4),(2,3),(2,4)],5)                                                 => 128
([(0,2),(0,3),(0,4),(1,2),(1,3),(1,4),(2,4),(3,4)],5)                                           => 256
([(0,2),(0,3),(0,4),(1,2),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                     => 512
([(0,1),(0,2),(0,3),(0,4),(1,2),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                               => 1024
([],6)                                                                                          => 1
([(4,5)],6)                                                                                     => 2
([(3,5),(4,5)],6)                                                                               => 4
([(2,5),(3,5),(4,5)],6)                                                                         => 8
([(1,5),(2,5),(3,5),(4,5)],6)                                                                   => 16
([(0,5),(1,5),(2,5),(3,5),(4,5)],6)                                                             => 32
([(2,5),(3,4)],6)                                                                               => 4
([(2,5),(3,4),(4,5)],6)                                                                         => 8
([(1,2),(3,5),(4,5)],6)                                                                         => 8
([(3,4),(3,5),(4,5)],6)                                                                         => 8
([(1,5),(2,5),(3,4),(4,5)],6)                                                                   => 16
([(0,1),(2,5),(3,5),(4,5)],6)                                                                   => 16
([(2,5),(3,4),(3,5),(4,5)],6)                                                                   => 16
([(0,5),(1,5),(2,5),(3,4),(4,5)],6)                                                             => 32
([(1,5),(2,5),(3,4),(3,5),(4,5)],6)                                                             => 32
([(0,5),(1,5),(2,5),(3,4),(3,5),(4,5)],6)                                                       => 64
([(2,4),(2,5),(3,4),(3,5)],6)                                                                   => 16
([(0,5),(1,5),(2,4),(3,4)],6)                                                                   => 16
([(1,5),(2,3),(2,4),(3,5),(4,5)],6)                                                             => 32
([(0,5),(1,5),(2,3),(3,4),(4,5)],6)                                                             => 32
([(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                             => 32
([(1,5),(2,4),(3,4),(3,5),(4,5)],6)                                                             => 32
([(0,5),(1,5),(2,4),(3,4),(4,5)],6)                                                             => 32
([(0,5),(1,5),(2,3),(2,4),(3,5),(4,5)],6)                                                       => 64
([(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                       => 64
([(0,5),(1,5),(2,4),(3,4),(3,5),(4,5)],6)                                                       => 64
([(0,5),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 128
([(1,4),(1,5),(2,4),(2,5),(3,4),(3,5)],6)                                                       => 64
([(0,5),(1,4),(2,4),(2,5),(3,4),(3,5)],6)                                                       => 64
([(0,5),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5)],6)                                                 => 128
([(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 128
([(0,5),(1,4),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 128
([(0,5),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 256
([(0,4),(0,5),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5)],6)                                           => 256
([(0,4),(0,5),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 512
([(0,5),(1,4),(2,3)],6)                                                                         => 8
([(1,5),(2,4),(3,4),(3,5)],6)                                                                   => 16
([(0,1),(2,5),(3,4),(4,5)],6)                                                                   => 16
([(1,2),(3,4),(3,5),(4,5)],6)                                                                   => 16
([(0,5),(1,4),(2,3),(3,5),(4,5)],6)                                                             => 32
([(1,4),(2,3),(2,5),(3,5),(4,5)],6)                                                             => 32
([(0,1),(2,5),(3,4),(3,5),(4,5)],6)                                                             => 32
([(0,4),(1,5),(2,3),(2,5),(3,5),(4,5)],6)                                                       => 64
([(1,4),(1,5),(2,3),(2,5),(3,5),(4,5)],6)                                                       => 64
([(0,5),(1,4),(1,5),(2,3),(2,5),(3,5),(4,5)],6)                                                 => 128
([(1,4),(1,5),(2,3),(2,5),(3,4)],6)                                                             => 32
([(0,5),(1,4),(2,3),(2,4),(3,5),(4,5)],6)                                                       => 64
([(1,2),(1,5),(2,4),(3,4),(3,5),(4,5)],6)                                                       => 64
([(0,5),(1,2),(1,4),(2,3),(3,5),(4,5)],6)                                                       => 64
([(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                                                       => 64
([(0,5),(1,4),(2,3),(3,4),(3,5),(4,5)],6)                                                       => 64
([(0,5),(1,2),(1,5),(2,4),(3,4),(3,5),(4,5)],6)                                                 => 128
([(0,5),(1,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 128
([(1,4),(1,5),(2,3),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 128
([(0,5),(1,4),(1,5),(2,3),(2,5),(3,4),(3,5),(4,5)],6)                                           => 256
([(0,5),(1,4),(2,3),(2,4),(3,5)],6)                                                             => 32
([(0,1),(2,4),(2,5),(3,4),(3,5)],6)                                                             => 32
([(0,5),(1,5),(2,3),(2,4),(3,4)],6)                                                             => 32
([(0,4),(1,2),(1,3),(2,5),(3,5),(4,5)],6)                                                       => 64
([(0,4),(1,2),(1,5),(2,5),(3,4),(3,5)],6)                                                       => 64
([(0,4),(1,2),(2,5),(3,4),(3,5),(4,5)],6)                                                       => 64
([(0,1),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                       => 64
([(0,4),(1,4),(2,3),(2,5),(3,5),(4,5)],6)                                                       => 64
([(0,3),(0,4),(1,2),(1,5),(2,5),(3,5),(4,5)],6)                                                 => 128
([(0,3),(1,4),(1,5),(2,4),(2,5),(3,5),(4,5)],6)                                                 => 128
([(0,4),(1,2),(1,5),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 128
([(0,1),(0,5),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 256
([(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                       => 64
([(0,5),(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                                                 => 128
([(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 128
([(0,5),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 256
([(0,1),(0,5),(1,4),(2,4),(2,5),(3,4),(3,5)],6)                                                 => 128
([(0,3),(0,5),(1,3),(1,5),(2,4),(2,5),(3,4),(4,5)],6)                                           => 256
([(0,3),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 256
([(0,5),(1,4),(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                                           => 256
([(0,1),(0,5),(1,4),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 256
([(0,4),(0,5),(1,4),(1,5),(2,3),(2,5),(3,4),(3,5),(4,5)],6)                                     => 512
([(0,5),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                                           => 256
([(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 256
([(0,5),(1,4),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 256
([(0,5),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 512
([(0,4),(0,5),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                                     => 512
([(0,4),(0,5),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 1024
([(0,5),(1,3),(1,4),(2,3),(2,4),(3,5),(4,5)],6)                                                 => 128
([(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                                                 => 128
([(0,5),(1,3),(1,4),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                                           => 256
([(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                                           => 256
([(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                                     => 512
([(0,4),(0,5),(1,2),(1,3),(2,5),(3,4)],6)                                                       => 64
([(0,3),(0,5),(1,2),(1,5),(2,4),(3,4),(4,5)],6)                                                 => 128
([(0,5),(1,2),(1,4),(2,3),(3,4),(3,5),(4,5)],6)                                                 => 128
([(0,1),(0,2),(1,5),(2,4),(3,4),(3,5),(4,5)],6)                                                 => 128
([(0,5),(1,4),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                                                 => 128
([(0,5),(1,3),(1,4),(2,4),(2,5),(3,4),(3,5)],6)                                                 => 128
([(0,1),(0,5),(1,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 256
([(0,4),(1,3),(1,5),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                                           => 256
([(0,4),(0,5),(1,3),(1,5),(2,3),(2,4),(3,5),(4,5)],6)                                           => 256
([(0,4),(0,5),(1,3),(1,5),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                                     => 512
([(0,4),(0,5),(1,2),(1,3),(2,4),(2,5),(3,4),(3,5)],6)                                           => 256
([(0,5),(1,2),(1,3),(1,4),(2,3),(2,4),(3,5),(4,5)],6)                                           => 256
([(0,4),(0,5),(1,2),(1,3),(1,5),(2,4),(2,5),(3,4),(3,5)],6)                                     => 512
([(0,4),(0,5),(1,2),(1,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 512
([(0,4),(0,5),(1,2),(1,3),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 1024
([(0,5),(1,2),(1,3),(1,4),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 512
([(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 512
([(0,5),(1,3),(1,4),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 512
([(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 1024
([(0,4),(0,5),(1,2),(1,4),(2,3),(2,5),(3,4),(3,5),(4,5)],6)                                     => 512
([(0,4),(0,5),(1,3),(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                                     => 512
([(0,4),(0,5),(1,3),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 1024
([(0,4),(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                         => 2048
([(0,3),(0,4),(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5)],6)                                     => 512
([(0,1),(0,2),(0,3),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 1024
([(0,4),(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                               => 1024
([(0,3),(0,4),(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                         => 2048
([(0,3),(0,4),(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                   => 4096
([(0,4),(0,5),(1,2),(1,3),(2,3),(4,5)],6)                                                       => 64
([(0,2),(1,4),(1,5),(2,3),(3,4),(3,5),(4,5)],6)                                                 => 128
([(0,1),(0,5),(1,5),(2,3),(2,4),(3,4),(4,5)],6)                                                 => 128
([(0,1),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 128
([(0,1),(0,5),(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                                           => 256
([(0,1),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 256
([(0,1),(0,5),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 512
([(0,4),(0,5),(1,2),(1,3),(2,3),(2,5),(3,4),(4,5)],6)                                           => 256
([(0,4),(0,5),(1,2),(1,3),(1,4),(2,3),(2,5),(3,5),(4,5)],6)                                     => 512
([(0,3),(1,2),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 512
([(0,3),(0,5),(1,2),(1,4),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 512
([(0,1),(0,5),(1,4),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 512
([(0,3),(0,5),(1,2),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 1024
([(0,3),(0,4),(0,5),(1,2),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5)],6)                               => 1024
([(0,3),(0,4),(0,5),(1,2),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                         => 2048
([(0,4),(0,5),(1,3),(1,5),(2,3),(2,4),(2,5),(3,4)],6)                                           => 256
([(0,1),(0,5),(1,4),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                                           => 256
([(0,3),(0,4),(1,2),(1,4),(1,5),(2,3),(2,5),(3,5),(4,5)],6)                                     => 512
([(0,3),(0,4),(0,5),(1,2),(1,4),(1,5),(2,3),(2,5),(3,5),(4,5)],6)                               => 1024
([(0,3),(0,4),(0,5),(1,2),(1,4),(1,5),(2,3),(2,5),(3,4)],6)                                     => 512
([(0,1),(0,3),(0,5),(1,2),(1,4),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 1024
([(0,4),(0,5),(1,2),(1,3),(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                               => 1024
([(0,1),(0,4),(0,5),(1,3),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                         => 2048
([(0,3),(0,4),(0,5),(1,2),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                   => 4096
([(0,2),(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                               => 1024
([(0,4),(0,5),(1,2),(1,3),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 1024
([(0,4),(0,5),(1,2),(1,3),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                         => 2048
([(0,5),(1,2),(1,3),(1,4),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 1024
([(1,2),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 1024
([(0,5),(1,2),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                         => 2048
([(0,4),(0,5),(1,2),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                   => 4096
([(0,3),(0,4),(0,5),(1,2),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)             => 8192
([(0,3),(0,4),(0,5),(1,2),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                         => 2048
([(0,4),(0,5),(1,2),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                         => 2048
([(0,1),(0,4),(0,5),(1,2),(1,3),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                         => 2048
([(0,3),(0,4),(0,5),(1,2),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                   => 4096
([(0,2),(0,3),(0,4),(0,5),(1,2),(1,3),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5)],6)                   => 4096
([(0,2),(0,3),(0,4),(0,5),(1,2),(1,3),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)             => 8192
([(0,2),(0,3),(0,4),(0,5),(1,2),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)       => 16384
([(0,1),(0,2),(0,3),(0,4),(0,5),(1,2),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6) => 32768

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Created: Dec 23, 2015 at 09:06 by Martin Rubey

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Last Updated: Dec 23, 2015 at 09:06 by Martin Rubey