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Statistic identifier: St001706

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Collection: Graphs

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Description: The number of closed sets in a graph.

A subset $S$ of the set of vertices is a closed set, if for any pair of distinct elements of $S$ the intersection of the corresponding neighbourhoods is a subset of $S$:
$$
\forall a, b\in S: N(a)\cap N(b) \subseteq S.
$$

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References: [1]   Koh, K. M., Poh, K. S. On the spectrum of the closed-set lattice of a graph [[MathSciNet:1165806]]

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Code:
def is_closed_set(G, S):
    for u, v in Subsets(S, 2):
        if not set(G[u]).intersection(G[v]).issubset(S):
            return False
    return True

def statistic(G):
    return sum(1 for S in Subsets(G.vertices()) if is_closed_set(G, S))

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

([],0)                                                                                          => 1
([],1)                                                                                          => 2
([],2)                                                                                          => 4
([(0,1)],2)                                                                                     => 4
([],3)                                                                                          => 8
([(1,2)],3)                                                                                     => 8
([(0,2),(1,2)],3)                                                                               => 7
([(0,1),(0,2),(1,2)],3)                                                                         => 5
([],4)                                                                                          => 16
([(2,3)],4)                                                                                     => 16
([(1,3),(2,3)],4)                                                                               => 14
([(0,3),(1,3),(2,3)],4)                                                                         => 12
([(0,3),(1,2)],4)                                                                               => 16
([(0,3),(1,2),(2,3)],4)                                                                         => 12
([(1,2),(1,3),(2,3)],4)                                                                         => 10
([(0,3),(1,2),(1,3),(2,3)],4)                                                                   => 8
([(0,2),(0,3),(1,2),(1,3)],4)                                                                   => 10
([(0,2),(0,3),(1,2),(1,3),(2,3)],4)                                                             => 6
([(0,1),(0,2),(0,3),(1,2),(1,3),(2,3)],4)                                                       => 6
([],5)                                                                                          => 32
([(3,4)],5)                                                                                     => 32
([(2,4),(3,4)],5)                                                                               => 28
([(1,4),(2,4),(3,4)],5)                                                                         => 24
([(0,4),(1,4),(2,4),(3,4)],5)                                                                   => 21
([(1,4),(2,3)],5)                                                                               => 32
([(1,4),(2,3),(3,4)],5)                                                                         => 24
([(0,1),(2,4),(3,4)],5)                                                                         => 28
([(2,3),(2,4),(3,4)],5)                                                                         => 20
([(0,4),(1,4),(2,3),(3,4)],5)                                                                   => 20
([(1,4),(2,3),(2,4),(3,4)],5)                                                                   => 16
([(0,4),(1,4),(2,3),(2,4),(3,4)],5)                                                             => 13
([(1,3),(1,4),(2,3),(2,4)],5)                                                                   => 20
([(0,4),(1,2),(1,3),(2,4),(3,4)],5)                                                             => 16
([(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                                             => 12
([(0,4),(1,3),(2,3),(2,4),(3,4)],5)                                                             => 13
([(0,4),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                                       => 9
([(0,3),(0,4),(1,3),(1,4),(2,3),(2,4)],5)                                                       => 13
([(0,3),(0,4),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                                 => 7
([(0,4),(1,3),(2,3),(2,4)],5)                                                                   => 21
([(0,1),(2,3),(2,4),(3,4)],5)                                                                   => 20
([(0,3),(1,2),(1,4),(2,4),(3,4)],5)                                                             => 14
([(0,3),(0,4),(1,2),(1,4),(2,4),(3,4)],5)                                                       => 9
([(0,3),(0,4),(1,2),(1,4),(2,3)],5)                                                             => 17
([(0,1),(0,4),(1,3),(2,3),(2,4),(3,4)],5)                                                       => 11
([(0,3),(0,4),(1,2),(1,4),(2,3),(2,4),(3,4)],5)                                                 => 7
([(0,4),(1,2),(1,3),(2,3),(2,4),(3,4)],5)                                                       => 10
([(1,2),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                                       => 12
([(0,4),(1,2),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                                 => 9
([(0,3),(0,4),(1,2),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                           => 7
([(0,3),(0,4),(1,2),(1,3),(1,4),(2,3),(2,4)],5)                                                 => 9
([(0,2),(0,3),(0,4),(1,2),(1,3),(1,4),(2,4),(3,4)],5)                                           => 7
([(0,2),(0,3),(0,4),(1,2),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                     => 7
([(0,1),(0,2),(0,3),(0,4),(1,2),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                               => 7
([],6)                                                                                          => 64
([(4,5)],6)                                                                                     => 64
([(3,5),(4,5)],6)                                                                               => 56
([(2,5),(3,5),(4,5)],6)                                                                         => 48
([(1,5),(2,5),(3,5),(4,5)],6)                                                                   => 42
([(0,5),(1,5),(2,5),(3,5),(4,5)],6)                                                             => 38
([(2,5),(3,4)],6)                                                                               => 64
([(2,5),(3,4),(4,5)],6)                                                                         => 48
([(1,2),(3,5),(4,5)],6)                                                                         => 56
([(3,4),(3,5),(4,5)],6)                                                                         => 40
([(1,5),(2,5),(3,4),(4,5)],6)                                                                   => 40
([(0,1),(2,5),(3,5),(4,5)],6)                                                                   => 48
([(2,5),(3,4),(3,5),(4,5)],6)                                                                   => 32
([(0,5),(1,5),(2,5),(3,4),(4,5)],6)                                                             => 34
([(1,5),(2,5),(3,4),(3,5),(4,5)],6)                                                             => 26
([(0,5),(1,5),(2,5),(3,4),(3,5),(4,5)],6)                                                       => 22
([(2,4),(2,5),(3,4),(3,5)],6)                                                                   => 40
([(0,5),(1,5),(2,4),(3,4)],6)                                                                   => 49
([(1,5),(2,3),(2,4),(3,5),(4,5)],6)                                                             => 32
([(0,5),(1,5),(2,3),(3,4),(4,5)],6)                                                             => 35
([(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                             => 24
([(1,5),(2,4),(3,4),(3,5),(4,5)],6)                                                             => 26
([(0,5),(1,5),(2,4),(3,4),(4,5)],6)                                                             => 33
([(0,5),(1,5),(2,3),(2,4),(3,5),(4,5)],6)                                                       => 26
([(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                       => 18
([(0,5),(1,5),(2,4),(3,4),(3,5),(4,5)],6)                                                       => 21
([(0,5),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 14
([(1,4),(1,5),(2,4),(2,5),(3,4),(3,5)],6)                                                       => 26
([(0,5),(1,4),(2,4),(2,5),(3,4),(3,5)],6)                                                       => 26
([(0,5),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5)],6)                                                 => 20
([(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 14
([(0,5),(1,4),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 14
([(0,5),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 10
([(0,4),(0,5),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5)],6)                                           => 16
([(0,4),(0,5),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 8
([(0,5),(1,4),(2,3)],6)                                                                         => 64
([(1,5),(2,4),(3,4),(3,5)],6)                                                                   => 42
([(0,1),(2,5),(3,4),(4,5)],6)                                                                   => 48
([(1,2),(3,4),(3,5),(4,5)],6)                                                                   => 40
([(0,5),(1,4),(2,3),(3,5),(4,5)],6)                                                             => 34
([(1,4),(2,3),(2,5),(3,5),(4,5)],6)                                                             => 28
([(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)                                                       => 22
([(1,4),(1,5),(2,3),(2,5),(3,5),(4,5)],6)                                                       => 18
([(0,5),(1,4),(1,5),(2,3),(2,5),(3,5),(4,5)],6)                                                 => 14
([(1,4),(1,5),(2,3),(2,5),(3,4)],6)                                                             => 34
([(0,5),(1,4),(2,3),(2,4),(3,5),(4,5)],6)                                                       => 25
([(1,2),(1,5),(2,4),(3,4),(3,5),(4,5)],6)                                                       => 22
([(0,5),(1,2),(1,4),(2,3),(3,5),(4,5)],6)                                                       => 28
([(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                                                       => 20
([(0,5),(1,4),(2,3),(3,4),(3,5),(4,5)],6)                                                       => 22
([(0,5),(1,2),(1,5),(2,4),(3,4),(3,5),(4,5)],6)                                                 => 17
([(0,5),(1,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 15
([(1,4),(1,5),(2,3),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 14
([(0,5),(1,4),(1,5),(2,3),(2,5),(3,4),(3,5),(4,5)],6)                                           => 10
([(0,5),(1,4),(2,3),(2,4),(3,5)],6)                                                             => 37
([(0,1),(2,4),(2,5),(3,4),(3,5)],6)                                                             => 40
([(0,5),(1,5),(2,3),(2,4),(3,4)],6)                                                             => 35
([(0,4),(1,2),(1,3),(2,5),(3,5),(4,5)],6)                                                       => 28
([(0,4),(1,2),(1,5),(2,5),(3,4),(3,5)],6)                                                       => 25
([(0,4),(1,2),(2,5),(3,4),(3,5),(4,5)],6)                                                       => 23
([(0,1),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                       => 24
([(0,4),(1,4),(2,3),(2,5),(3,5),(4,5)],6)                                                       => 23
([(0,3),(0,4),(1,2),(1,5),(2,5),(3,5),(4,5)],6)                                                 => 18
([(0,3),(1,4),(1,5),(2,4),(2,5),(3,5),(4,5)],6)                                                 => 16
([(0,4),(1,2),(1,5),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 15
([(0,1),(0,5),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 10
([(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                       => 24
([(0,5),(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                                                 => 16
([(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 18
([(0,5),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 14
([(0,1),(0,5),(1,4),(2,4),(2,5),(3,4),(3,5)],6)                                                 => 22
([(0,3),(0,5),(1,3),(1,5),(2,4),(2,5),(3,4),(4,5)],6)                                           => 14
([(0,3),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 12
([(0,5),(1,4),(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                                           => 11
([(0,1),(0,5),(1,4),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 12
([(0,4),(0,5),(1,4),(1,5),(2,3),(2,5),(3,4),(3,5),(4,5)],6)                                     => 8
([(0,5),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                                           => 14
([(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 14
([(0,5),(1,4),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 14
([(0,5),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 10
([(0,4),(0,5),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                                     => 12
([(0,4),(0,5),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 8
([(0,5),(1,3),(1,4),(2,3),(2,4),(3,5),(4,5)],6)                                                 => 20
([(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                                                 => 18
([(0,5),(1,3),(1,4),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                                           => 13
([(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                                           => 14
([(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                                     => 10
([(0,4),(0,5),(1,2),(1,3),(2,5),(3,4)],6)                                                       => 29
([(0,3),(0,5),(1,2),(1,5),(2,4),(3,4),(4,5)],6)                                                 => 21
([(0,5),(1,2),(1,4),(2,3),(3,4),(3,5),(4,5)],6)                                                 => 18
([(0,1),(0,2),(1,5),(2,4),(3,4),(3,5),(4,5)],6)                                                 => 19
([(0,5),(1,4),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                                                 => 18
([(0,5),(1,3),(1,4),(2,4),(2,5),(3,4),(3,5)],6)                                                 => 18
([(0,1),(0,5),(1,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 13
([(0,4),(1,3),(1,5),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                                           => 12
([(0,4),(0,5),(1,3),(1,5),(2,3),(2,4),(3,5),(4,5)],6)                                           => 12
([(0,4),(0,5),(1,3),(1,5),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                                     => 8
([(0,4),(0,5),(1,2),(1,3),(2,4),(2,5),(3,4),(3,5)],6)                                           => 17
([(0,5),(1,2),(1,3),(1,4),(2,3),(2,4),(3,5),(4,5)],6)                                           => 16
([(0,4),(0,5),(1,2),(1,3),(1,5),(2,4),(2,5),(3,4),(3,5)],6)                                     => 12
([(0,4),(0,5),(1,2),(1,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 11
([(0,4),(0,5),(1,2),(1,3),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 8
([(0,5),(1,2),(1,3),(1,4),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 11
([(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 14
([(0,5),(1,3),(1,4),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 11
([(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 10
([(0,4),(0,5),(1,2),(1,4),(2,3),(2,5),(3,4),(3,5),(4,5)],6)                                     => 10
([(0,4),(0,5),(1,3),(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                                     => 8
([(0,4),(0,5),(1,3),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 8
([(0,4),(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                         => 8
([(0,3),(0,4),(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5)],6)                                     => 17
([(0,1),(0,2),(0,3),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 11
([(0,4),(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                               => 10
([(0,3),(0,4),(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                         => 8
([(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)                   => 8
([(0,4),(0,5),(1,2),(1,3),(2,3),(4,5)],6)                                                       => 25
([(0,2),(1,4),(1,5),(2,3),(3,4),(3,5),(4,5)],6)                                                 => 18
([(0,1),(0,5),(1,5),(2,3),(2,4),(3,4),(4,5)],6)                                                 => 17
([(0,1),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 24
([(0,1),(0,5),(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                                           => 12
([(0,1),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 16
([(0,1),(0,5),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 10
([(0,4),(0,5),(1,2),(1,3),(2,3),(2,5),(3,4),(4,5)],6)                                           => 13
([(0,4),(0,5),(1,2),(1,3),(1,4),(2,3),(2,5),(3,5),(4,5)],6)                                     => 10
([(0,3),(1,2),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 12
([(0,3),(0,5),(1,2),(1,4),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 9
([(0,1),(0,5),(1,4),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 12
([(0,3),(0,5),(1,2),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 8
([(0,3),(0,4),(0,5),(1,2),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5)],6)                               => 8
([(0,3),(0,4),(0,5),(1,2),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                         => 8
([(0,4),(0,5),(1,3),(1,5),(2,3),(2,4),(2,5),(3,4)],6)                                           => 15
([(0,1),(0,5),(1,4),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                                           => 14
([(0,3),(0,4),(1,2),(1,4),(1,5),(2,3),(2,5),(3,5),(4,5)],6)                                     => 10
([(0,3),(0,4),(0,5),(1,2),(1,4),(1,5),(2,3),(2,5),(3,5),(4,5)],6)                               => 8
([(0,3),(0,4),(0,5),(1,2),(1,4),(1,5),(2,3),(2,5),(3,4)],6)                                     => 13
([(0,1),(0,3),(0,5),(1,2),(1,4),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 9
([(0,4),(0,5),(1,2),(1,3),(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                               => 8
([(0,1),(0,4),(0,5),(1,3),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                         => 8
([(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)                   => 8
([(0,2),(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                               => 10
([(0,4),(0,5),(1,2),(1,3),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 9
([(0,4),(0,5),(1,2),(1,3),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                         => 8
([(0,5),(1,2),(1,3),(1,4),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 11
([(1,2),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 14
([(0,5),(1,2),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                         => 10
([(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)                   => 8
([(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)             => 8
([(0,3),(0,4),(0,5),(1,2),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                         => 8
([(0,4),(0,5),(1,2),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                         => 10
([(0,1),(0,4),(0,5),(1,2),(1,3),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                         => 9
([(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)                   => 8
([(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)                   => 8
([(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)             => 8
([(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)       => 8
([(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) => 8

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Created: Mar 31, 2021 at 21:51 by Martin Rubey

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Last Updated: Mar 31, 2021 at 21:51 by Martin Rubey