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-----------------------------------------------------------------------------
Statistic identifier: St000322

-----------------------------------------------------------------------------
Collection: Graphs

-----------------------------------------------------------------------------
Description: The skewness of a graph.

For a graph $G$, the '''skewness''' of $G$ is the minimum number of edges of $G$ whose removal results in a planar graph.

-----------------------------------------------------------------------------
References: [1]   Cimikowski, R. J. Graph planarization and skewness [[MathSciNet:1208914]]
[2]   [[wikipedia:Planarization]]
[3]   [[http://mathworld.wolfram.com/GraphSkewness.html]]

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Code:
@cached_function
def statistic(G):
    if G.is_planar():
        return 0
    bound = G.size()
    for e in G.edges(labels=False):
        H = G.copy(immutable=False)
        H.delete_edge(e)
        bound = min(bound, 1+statistic(H.canonical_label().copy(immutable=True)))
    return bound


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

([],1)                                                                                          => 0
([],2)                                                                                          => 0
([(0,1)],2)                                                                                     => 0
([],3)                                                                                          => 0
([(1,2)],3)                                                                                     => 0
([(0,2),(1,2)],3)                                                                               => 0
([(0,1),(0,2),(1,2)],3)                                                                         => 0
([],4)                                                                                          => 0
([(2,3)],4)                                                                                     => 0
([(1,3),(2,3)],4)                                                                               => 0
([(0,3),(1,3),(2,3)],4)                                                                         => 0
([(0,3),(1,2)],4)                                                                               => 0
([(0,3),(1,2),(2,3)],4)                                                                         => 0
([(1,2),(1,3),(2,3)],4)                                                                         => 0
([(0,3),(1,2),(1,3),(2,3)],4)                                                                   => 0
([(0,2),(0,3),(1,2),(1,3)],4)                                                                   => 0
([(0,2),(0,3),(1,2),(1,3),(2,3)],4)                                                             => 0
([(0,1),(0,2),(0,3),(1,2),(1,3),(2,3)],4)                                                       => 0
([],5)                                                                                          => 0
([(3,4)],5)                                                                                     => 0
([(2,4),(3,4)],5)                                                                               => 0
([(1,4),(2,4),(3,4)],5)                                                                         => 0
([(0,4),(1,4),(2,4),(3,4)],5)                                                                   => 0
([(1,4),(2,3)],5)                                                                               => 0
([(1,4),(2,3),(3,4)],5)                                                                         => 0
([(0,1),(2,4),(3,4)],5)                                                                         => 0
([(2,3),(2,4),(3,4)],5)                                                                         => 0
([(0,4),(1,4),(2,3),(3,4)],5)                                                                   => 0
([(1,4),(2,3),(2,4),(3,4)],5)                                                                   => 0
([(0,4),(1,4),(2,3),(2,4),(3,4)],5)                                                             => 0
([(1,3),(1,4),(2,3),(2,4)],5)                                                                   => 0
([(0,4),(1,2),(1,3),(2,4),(3,4)],5)                                                             => 0
([(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                                             => 0
([(0,4),(1,3),(2,3),(2,4),(3,4)],5)                                                             => 0
([(0,4),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                                       => 0
([(0,3),(0,4),(1,3),(1,4),(2,3),(2,4)],5)                                                       => 0
([(0,3),(0,4),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                                 => 0
([(0,4),(1,3),(2,3),(2,4)],5)                                                                   => 0
([(0,1),(2,3),(2,4),(3,4)],5)                                                                   => 0
([(0,3),(1,2),(1,4),(2,4),(3,4)],5)                                                             => 0
([(0,3),(0,4),(1,2),(1,4),(2,4),(3,4)],5)                                                       => 0
([(0,3),(0,4),(1,2),(1,4),(2,3)],5)                                                             => 0
([(0,1),(0,4),(1,3),(2,3),(2,4),(3,4)],5)                                                       => 0
([(0,3),(0,4),(1,2),(1,4),(2,3),(2,4),(3,4)],5)                                                 => 0
([(0,4),(1,2),(1,3),(2,3),(2,4),(3,4)],5)                                                       => 0
([(1,2),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                                       => 0
([(0,4),(1,2),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                                 => 0
([(0,3),(0,4),(1,2),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                           => 0
([(0,3),(0,4),(1,2),(1,3),(1,4),(2,3),(2,4)],5)                                                 => 0
([(0,2),(0,3),(0,4),(1,2),(1,3),(1,4),(2,4),(3,4)],5)                                           => 0
([(0,2),(0,3),(0,4),(1,2),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                     => 0
([(0,1),(0,2),(0,3),(0,4),(1,2),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                               => 1
([],6)                                                                                          => 0
([(4,5)],6)                                                                                     => 0
([(3,5),(4,5)],6)                                                                               => 0
([(2,5),(3,5),(4,5)],6)                                                                         => 0
([(1,5),(2,5),(3,5),(4,5)],6)                                                                   => 0
([(0,5),(1,5),(2,5),(3,5),(4,5)],6)                                                             => 0
([(2,5),(3,4)],6)                                                                               => 0
([(2,5),(3,4),(4,5)],6)                                                                         => 0
([(1,2),(3,5),(4,5)],6)                                                                         => 0
([(3,4),(3,5),(4,5)],6)                                                                         => 0
([(1,5),(2,5),(3,4),(4,5)],6)                                                                   => 0
([(0,1),(2,5),(3,5),(4,5)],6)                                                                   => 0
([(2,5),(3,4),(3,5),(4,5)],6)                                                                   => 0
([(0,5),(1,5),(2,5),(3,4),(4,5)],6)                                                             => 0
([(1,5),(2,5),(3,4),(3,5),(4,5)],6)                                                             => 0
([(0,5),(1,5),(2,5),(3,4),(3,5),(4,5)],6)                                                       => 0
([(2,4),(2,5),(3,4),(3,5)],6)                                                                   => 0
([(0,5),(1,5),(2,4),(3,4)],6)                                                                   => 0
([(1,5),(2,3),(2,4),(3,5),(4,5)],6)                                                             => 0
([(0,5),(1,5),(2,3),(3,4),(4,5)],6)                                                             => 0
([(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                             => 0
([(1,5),(2,4),(3,4),(3,5),(4,5)],6)                                                             => 0
([(0,5),(1,5),(2,4),(3,4),(4,5)],6)                                                             => 0
([(0,5),(1,5),(2,3),(2,4),(3,5),(4,5)],6)                                                       => 0
([(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                       => 0
([(0,5),(1,5),(2,4),(3,4),(3,5),(4,5)],6)                                                       => 0
([(0,5),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 0
([(1,4),(1,5),(2,4),(2,5),(3,4),(3,5)],6)                                                       => 0
([(0,5),(1,4),(2,4),(2,5),(3,4),(3,5)],6)                                                       => 0
([(0,5),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5)],6)                                                 => 0
([(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 0
([(0,5),(1,4),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 0
([(0,5),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 0
([(0,4),(0,5),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5)],6)                                           => 0
([(0,4),(0,5),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 0
([(0,5),(1,4),(2,3)],6)                                                                         => 0
([(1,5),(2,4),(3,4),(3,5)],6)                                                                   => 0
([(0,1),(2,5),(3,4),(4,5)],6)                                                                   => 0
([(1,2),(3,4),(3,5),(4,5)],6)                                                                   => 0
([(0,5),(1,4),(2,3),(3,5),(4,5)],6)                                                             => 0
([(1,4),(2,3),(2,5),(3,5),(4,5)],6)                                                             => 0
([(0,1),(2,5),(3,4),(3,5),(4,5)],6)                                                             => 0
([(0,4),(1,5),(2,3),(2,5),(3,5),(4,5)],6)                                                       => 0
([(1,4),(1,5),(2,3),(2,5),(3,5),(4,5)],6)                                                       => 0
([(0,5),(1,4),(1,5),(2,3),(2,5),(3,5),(4,5)],6)                                                 => 0
([(1,4),(1,5),(2,3),(2,5),(3,4)],6)                                                             => 0
([(0,5),(1,4),(2,3),(2,4),(3,5),(4,5)],6)                                                       => 0
([(1,2),(1,5),(2,4),(3,4),(3,5),(4,5)],6)                                                       => 0
([(0,5),(1,2),(1,4),(2,3),(3,5),(4,5)],6)                                                       => 0
([(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                                                       => 0
([(0,5),(1,4),(2,3),(3,4),(3,5),(4,5)],6)                                                       => 0
([(0,5),(1,2),(1,5),(2,4),(3,4),(3,5),(4,5)],6)                                                 => 0
([(0,5),(1,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 0
([(1,4),(1,5),(2,3),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 0
([(0,5),(1,4),(1,5),(2,3),(2,5),(3,4),(3,5),(4,5)],6)                                           => 0
([(0,5),(1,4),(2,3),(2,4),(3,5)],6)                                                             => 0
([(0,1),(2,4),(2,5),(3,4),(3,5)],6)                                                             => 0
([(0,5),(1,5),(2,3),(2,4),(3,4)],6)                                                             => 0
([(0,4),(1,2),(1,3),(2,5),(3,5),(4,5)],6)                                                       => 0
([(0,4),(1,2),(1,5),(2,5),(3,4),(3,5)],6)                                                       => 0
([(0,4),(1,2),(2,5),(3,4),(3,5),(4,5)],6)                                                       => 0
([(0,1),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                       => 0
([(0,4),(1,4),(2,3),(2,5),(3,5),(4,5)],6)                                                       => 0
([(0,3),(0,4),(1,2),(1,5),(2,5),(3,5),(4,5)],6)                                                 => 0
([(0,3),(1,4),(1,5),(2,4),(2,5),(3,5),(4,5)],6)                                                 => 0
([(0,4),(1,2),(1,5),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 0
([(0,1),(0,5),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 0
([(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                       => 0
([(0,5),(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                                                 => 0
([(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 0
([(0,5),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 0
([(0,1),(0,5),(1,4),(2,4),(2,5),(3,4),(3,5)],6)                                                 => 0
([(0,3),(0,5),(1,3),(1,5),(2,4),(2,5),(3,4),(4,5)],6)                                           => 0
([(0,3),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 0
([(0,5),(1,4),(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                                           => 0
([(0,1),(0,5),(1,4),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 0
([(0,4),(0,5),(1,4),(1,5),(2,3),(2,5),(3,4),(3,5),(4,5)],6)                                     => 0
([(0,5),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                                           => 0
([(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 0
([(0,5),(1,4),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 0
([(0,5),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 0
([(0,4),(0,5),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                                     => 0
([(0,4),(0,5),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 0
([(0,5),(1,3),(1,4),(2,3),(2,4),(3,5),(4,5)],6)                                                 => 0
([(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                                                 => 0
([(0,5),(1,3),(1,4),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                                           => 0
([(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                                           => 0
([(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                                     => 0
([(0,4),(0,5),(1,2),(1,3),(2,5),(3,4)],6)                                                       => 0
([(0,3),(0,5),(1,2),(1,5),(2,4),(3,4),(4,5)],6)                                                 => 0
([(0,5),(1,2),(1,4),(2,3),(3,4),(3,5),(4,5)],6)                                                 => 0
([(0,1),(0,2),(1,5),(2,4),(3,4),(3,5),(4,5)],6)                                                 => 0
([(0,5),(1,4),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                                                 => 0
([(0,5),(1,3),(1,4),(2,4),(2,5),(3,4),(3,5)],6)                                                 => 0
([(0,1),(0,5),(1,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 0
([(0,4),(1,3),(1,5),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                                           => 0
([(0,4),(0,5),(1,3),(1,5),(2,3),(2,4),(3,5),(4,5)],6)                                           => 0
([(0,4),(0,5),(1,3),(1,5),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                                     => 0
([(0,4),(0,5),(1,2),(1,3),(2,4),(2,5),(3,4),(3,5)],6)                                           => 0
([(0,5),(1,2),(1,3),(1,4),(2,3),(2,4),(3,5),(4,5)],6)                                           => 0
([(0,4),(0,5),(1,2),(1,3),(1,5),(2,4),(2,5),(3,4),(3,5)],6)                                     => 0
([(0,4),(0,5),(1,2),(1,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 0
([(0,4),(0,5),(1,2),(1,3),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 0
([(0,5),(1,2),(1,3),(1,4),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 0
([(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 0
([(0,5),(1,3),(1,4),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 0
([(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 0
([(0,4),(0,5),(1,2),(1,4),(2,3),(2,5),(3,4),(3,5),(4,5)],6)                                     => 0
([(0,4),(0,5),(1,3),(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                                     => 0
([(0,4),(0,5),(1,3),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 0
([(0,4),(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                         => 0
([(0,3),(0,4),(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5)],6)                                     => 1
([(0,1),(0,2),(0,3),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 1
([(0,4),(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                               => 0
([(0,3),(0,4),(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                         => 1
([(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)                   => 1
([(0,4),(0,5),(1,2),(1,3),(2,3),(4,5)],6)                                                       => 0
([(0,2),(1,4),(1,5),(2,3),(3,4),(3,5),(4,5)],6)                                                 => 0
([(0,1),(0,5),(1,5),(2,3),(2,4),(3,4),(4,5)],6)                                                 => 0
([(0,1),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 0
([(0,1),(0,5),(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                                           => 0
([(0,1),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 0
([(0,1),(0,5),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 0
([(0,4),(0,5),(1,2),(1,3),(2,3),(2,5),(3,4),(4,5)],6)                                           => 0
([(0,4),(0,5),(1,2),(1,3),(1,4),(2,3),(2,5),(3,5),(4,5)],6)                                     => 0
([(0,3),(1,2),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 0
([(0,3),(0,5),(1,2),(1,4),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 0
([(0,1),(0,5),(1,4),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 0
([(0,3),(0,5),(1,2),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 0
([(0,3),(0,4),(0,5),(1,2),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5)],6)                               => 0
([(0,3),(0,4),(0,5),(1,2),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                         => 0
([(0,4),(0,5),(1,3),(1,5),(2,3),(2,4),(2,5),(3,4)],6)                                           => 0
([(0,1),(0,5),(1,4),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                                           => 0
([(0,3),(0,4),(1,2),(1,4),(1,5),(2,3),(2,5),(3,5),(4,5)],6)                                     => 0
([(0,3),(0,4),(0,5),(1,2),(1,4),(1,5),(2,3),(2,5),(3,5),(4,5)],6)                               => 0
([(0,3),(0,4),(0,5),(1,2),(1,4),(1,5),(2,3),(2,5),(3,4)],6)                                     => 0
([(0,1),(0,3),(0,5),(1,2),(1,4),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 0
([(0,4),(0,5),(1,2),(1,3),(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                               => 0
([(0,1),(0,4),(0,5),(1,3),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                         => 0
([(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)                   => 0
([(0,2),(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                               => 0
([(0,4),(0,5),(1,2),(1,3),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 0
([(0,4),(0,5),(1,2),(1,3),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                         => 0
([(0,5),(1,2),(1,3),(1,4),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 0
([(1,2),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 1
([(0,5),(1,2),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                         => 1
([(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)                   => 1
([(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)             => 1
([(0,3),(0,4),(0,5),(1,2),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                         => 0
([(0,4),(0,5),(1,2),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                         => 1
([(0,1),(0,4),(0,5),(1,2),(1,3),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                         => 1
([(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)                   => 1
([(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)                   => 0
([(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)             => 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)       => 2
([(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) => 3
([(0,6),(1,6),(2,6),(3,6),(4,6),(5,6)],7)                                                       => 0
([(0,6),(1,6),(2,6),(3,6),(4,5),(5,6)],7)                                                       => 0
([(0,6),(1,6),(2,6),(3,4),(4,5),(5,6)],7)                                                       => 0
([(0,6),(1,6),(2,6),(3,5),(4,5),(5,6)],7)                                                       => 0
([(0,6),(1,6),(2,5),(3,5),(4,5),(4,6)],7)                                                       => 0
([(0,6),(1,6),(2,5),(3,4),(4,6),(5,6)],7)                                                       => 0
([(0,6),(1,6),(2,3),(3,5),(4,5),(4,6)],7)                                                       => 0
([(0,6),(1,4),(2,3),(3,6),(4,5),(5,6)],7)                                                       => 0
([(0,6),(1,5),(2,5),(3,4),(4,6),(5,6)],7)                                                       => 0
([(0,5),(1,4),(2,3),(3,6),(4,6),(5,6)],7)                                                       => 0
([(0,6),(1,5),(2,3),(2,4),(3,5),(4,6)],7)                                                       => 0
([(0,1),(0,3),(0,4),(0,6),(1,2),(1,4),(1,5),(2,3),(2,5),(2,6),(3,5),(3,6),(4,5),(4,6),(5,6)],7) => 1
([(0,3),(0,5),(0,6),(1,2),(1,3),(1,4),(1,5),(2,4),(2,5),(2,6),(3,4),(3,6),(4,5),(4,6),(5,6)],7) => 1
([(0,4),(0,5),(0,6),(1,2),(1,3),(1,5),(1,6),(2,3),(2,4),(2,6),(3,4),(3,5),(4,5),(4,6),(5,6)],7) => 0
([(0,5),(0,6),(1,2),(1,3),(1,4),(1,6),(2,3),(2,4),(2,5),(3,4),(3,5),(3,6),(4,5),(4,6),(5,6)],7) => 1
([(0,2),(0,3),(0,6),(1,3),(1,4),(1,5),(1,6),(2,4),(2,5),(2,6),(3,4),(3,5),(4,5),(4,6),(5,6)],7) => 1
([(0,1),(0,5),(0,6),(1,3),(1,4),(2,3),(2,4),(2,5),(2,6),(3,4),(3,5),(3,6),(4,5),(4,6),(5,6)],7) => 2
([(0,3),(0,4),(0,6),(1,2),(1,5),(1,6),(2,3),(2,4),(2,5),(3,4),(3,5),(3,6),(4,5),(4,6),(5,6)],7) => 1
([(0,2),(0,6),(1,3),(1,4),(1,5),(1,6),(2,3),(2,4),(2,5),(3,4),(3,5),(3,6),(4,5),(4,6),(5,6)],7) => 2
([(0,5),(0,6),(1,2),(1,3),(1,4),(2,3),(2,4),(2,5),(2,6),(3,4),(3,5),(3,6),(4,5),(4,6),(5,6)],7) => 1
([(0,6),(1,2),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(2,6),(3,4),(3,5),(3,6),(4,5),(4,6),(5,6)],7) => 2
([(1,2),(1,3),(1,4),(1,5),(1,6),(2,3),(2,4),(2,5),(2,6),(3,4),(3,5),(3,6),(4,5),(4,6),(5,6)],7) => 3
([(0,8),(1,6),(2,6),(3,7),(4,5),(5,8),(6,7),(7,8)],9)                                           => 0
([(0,6),(1,6),(2,7),(3,7),(4,8),(5,7),(5,8),(6,8)],9)                                           => 0
([(0,7),(1,7),(2,6),(3,6),(4,5),(5,8),(6,8),(7,8)],9)                                           => 0
([(0,10),(1,7),(2,7),(3,8),(4,9),(5,6),(6,10),(7,9),(8,9),(8,10)],11)                           => 0
([(0,10),(1,8),(2,8),(3,7),(4,7),(5,6),(6,10),(7,9),(8,9),(9,10)],11)                           => 0
([(0,8),(1,8),(2,9),(3,7),(4,7),(5,6),(6,10),(7,10),(8,9),(9,10)],11)                           => 0
([(0,10),(1,9),(2,9),(3,7),(4,8),(5,8),(6,9),(6,10),(7,8),(7,10)],11)                           => 0
([(0,9),(1,9),(2,8),(3,8),(4,7),(5,7),(6,9),(6,10),(7,10),(8,10)],11)                           => 0
([(0,10),(1,9),(2,7),(3,7),(4,8),(5,8),(6,9),(6,10),(7,9),(8,10)],11)                           => 0
([(0,12),(1,8),(2,8),(3,9),(4,10),(5,11),(6,7),(7,12),(8,10),(9,11),(9,12),(10,11)],13)         => 0
([(0,12),(1,9),(2,9),(3,8),(4,8),(5,10),(6,7),(7,12),(8,11),(9,11),(10,11),(10,12)],13)         => 0
([(0,12),(1,8),(2,8),(3,9),(4,9),(5,10),(6,7),(7,12),(8,11),(9,10),(10,11),(11,12)],13)         => 0
([(0,9),(1,9),(2,10),(3,11),(4,8),(5,8),(6,7),(7,12),(8,12),(9,11),(10,11),(10,12)],13)         => 0
([(0,10),(1,10),(2,9),(3,9),(4,8),(5,8),(6,7),(7,12),(8,12),(9,11),(10,11),(11,12)],13)         => 0
([(0,8),(1,8),(2,9),(3,9),(4,11),(5,10),(6,7),(7,12),(8,10),(9,11),(10,12),(11,12)],13)         => 0
([(0,12),(1,11),(2,11),(3,8),(4,8),(5,9),(6,10),(7,11),(7,12),(8,10),(9,10),(9,12)],13)         => 0
([(0,11),(1,12),(2,12),(3,9),(4,9),(5,8),(6,8),(7,11),(7,12),(8,10),(9,10),(10,11)],13)         => 0
([(0,11),(1,11),(2,9),(3,9),(4,10),(5,8),(6,8),(7,11),(7,12),(8,12),(9,10),(10,12)],13)         => 0
([(0,12),(1,11),(2,9),(3,9),(4,10),(5,8),(6,8),(7,11),(7,12),(8,11),(9,10),(10,12)],13)         => 0
([(0,11),(1,9),(2,9),(3,8),(4,8),(5,10),(6,10),(7,11),(7,12),(8,12),(9,12),(10,11)],13)         => 0

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Created: Dec 09, 2015 at 11:47 by Christian Stump

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Last Updated: Dec 23, 2020 at 22:20 by Martin Rubey