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Statistic identifier: St001625

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Collection: Lattices

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Description: The Möbius invariant of a lattice.

The '''Möbius invariant''' of a lattice $L$ is the value of the Möbius function applied to least and greatest element, that is $\mu(L)=\mu_L(\hat{0},\hat{1})$, where $\hat{0}$ is the least element of $L$ and $\hat{1}$ is the greatest element of $L$.
For the definition of the Möbius function, see [[St000914]].

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References: 

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Code:
def statistic(L):
    return L.moebius_function(L.bottom(), L.top())

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Statistic values:

([],1)                                                            => 1
([(0,1)],2)                                                       => -1
([(0,2),(2,1)],3)                                                 => 0
([(0,1),(0,2),(1,3),(2,3)],4)                                     => 1
([(0,3),(2,1),(3,2)],4)                                           => 0
([(0,1),(0,2),(0,3),(1,4),(2,4),(3,4)],5)                         => 2
([(0,2),(0,3),(1,4),(2,4),(3,1)],5)                               => 1
([(0,3),(1,4),(2,4),(3,1),(3,2)],5)                               => 0
([(0,4),(2,3),(3,1),(4,2)],5)                                     => 0
([(0,2),(0,3),(2,4),(3,4),(4,1)],5)                               => 0
([(0,1),(0,2),(0,3),(0,4),(1,5),(2,5),(3,5),(4,5)],6)             => 3
([(0,2),(0,3),(0,4),(1,5),(2,5),(3,5),(4,1)],6)                   => 2
([(0,3),(0,4),(1,5),(2,5),(3,5),(4,1),(4,2)],6)                   => 1
([(0,4),(1,5),(2,5),(3,5),(4,1),(4,2),(4,3)],6)                   => 0
([(0,4),(1,5),(2,5),(3,2),(4,1),(4,3)],6)                         => 0
([(0,4),(1,5),(2,5),(4,1),(4,2),(5,3)],6)                         => 0
([(0,2),(0,4),(1,5),(2,5),(3,1),(4,3)],6)                         => 1
([(0,3),(1,5),(2,5),(3,4),(4,1),(4,2)],6)                         => 0
([(0,1),(0,2),(0,3),(1,5),(2,4),(3,4),(4,5)],6)                   => 1
([(0,2),(0,3),(2,5),(3,5),(4,1),(5,4)],6)                         => 0
([(0,2),(0,3),(0,4),(2,5),(3,5),(4,5),(5,1)],6)                   => 0
([(0,3),(0,4),(1,5),(2,5),(3,2),(4,1)],6)                         => 1
([(0,2),(0,3),(1,5),(2,4),(3,1),(3,4),(4,5)],6)                   => 0
([(0,5),(2,4),(3,2),(4,1),(5,3)],6)                               => 0
([(0,3),(0,4),(1,5),(3,5),(4,1),(5,2)],6)                         => 0
([(0,1),(0,2),(0,3),(0,4),(0,5),(1,6),(2,6),(3,6),(4,6),(5,6)],7) => 4
([(0,2),(0,3),(0,4),(0,5),(1,6),(2,6),(3,6),(4,6),(5,1)],7)       => 3
([(0,3),(0,4),(0,5),(1,6),(2,6),(3,6),(4,6),(5,1),(5,2)],7)       => 2
([(0,4),(0,5),(1,6),(2,6),(3,6),(4,6),(5,1),(5,2),(5,3)],7)       => 1
([(0,5),(1,6),(2,6),(3,6),(4,6),(5,1),(5,2),(5,3),(5,4)],7)       => 0
([(0,5),(1,6),(2,6),(3,6),(4,3),(5,1),(5,2),(5,4)],7)             => 0
([(0,4),(1,6),(2,5),(3,5),(4,1),(4,2),(4,3),(5,6)],7)             => 0
([(0,5),(1,6),(2,6),(3,6),(5,1),(5,2),(5,3),(6,4)],7)             => 0
([(0,3),(0,5),(1,6),(2,6),(3,6),(4,2),(5,1),(5,4)],7)             => 1
([(0,5),(1,6),(2,6),(3,6),(4,2),(4,3),(5,1),(5,4)],7)             => 0
([(0,3),(0,4),(1,5),(2,5),(3,6),(4,1),(4,2),(5,6)],7)             => 1
([(0,5),(2,6),(3,6),(4,1),(5,2),(5,3),(6,4)],7)                   => 0
([(0,5),(1,6),(2,6),(3,2),(4,1),(5,3),(5,4)],7)                   => 0
([(0,4),(1,6),(2,5),(3,1),(3,5),(4,2),(4,3),(5,6)],7)             => 0
([(0,2),(0,3),(0,5),(1,6),(2,6),(3,6),(4,1),(5,4)],7)             => 2
([(0,3),(0,4),(1,6),(2,6),(3,6),(4,5),(5,1),(5,2)],7)             => 1
([(0,4),(1,6),(2,6),(3,6),(4,5),(5,1),(5,2),(5,3)],7)             => 0
([(0,1),(0,2),(0,3),(0,4),(1,6),(2,6),(3,5),(4,5),(5,6)],7)       => 2
([(0,2),(0,3),(0,4),(1,5),(2,6),(3,6),(4,5),(6,1)],7)             => 1
([(0,3),(0,4),(1,5),(2,5),(3,6),(4,6),(6,1),(6,2)],7)             => 0
([(0,1),(0,2),(0,3),(0,4),(1,6),(2,6),(3,6),(4,5),(6,5)],7)       => 1
([(0,2),(0,3),(0,4),(2,6),(3,6),(4,6),(5,1),(6,5)],7)             => 0
([(0,2),(0,3),(0,4),(0,5),(2,6),(3,6),(4,6),(5,6),(6,1)],7)       => 0
([(0,2),(0,3),(0,4),(1,6),(2,5),(3,5),(4,1),(5,6)],7)             => 1
([(0,1),(0,2),(0,3),(1,5),(2,4),(3,4),(3,5),(4,6),(5,6)],7)       => 0
([(0,2),(0,3),(2,6),(3,6),(4,1),(5,4),(6,5)],7)                   => 0
([(0,2),(0,3),(0,4),(2,6),(3,5),(4,5),(5,6),(6,1)],7)             => 0
([(0,2),(0,3),(0,4),(1,5),(2,6),(3,6),(4,1),(4,6),(6,5)],7)       => 0
([(0,3),(0,4),(0,5),(1,6),(3,6),(4,6),(5,1),(6,2)],7)             => 0
([(0,3),(0,4),(0,5),(1,6),(2,6),(3,6),(4,2),(5,1)],7)             => 2
([(0,2),(0,3),(0,4),(1,6),(2,6),(3,5),(4,1),(4,5),(5,6)],7)       => 1
([(0,2),(0,4),(1,6),(2,5),(3,1),(4,3),(4,5),(5,6)],7)             => 0
([(0,3),(0,4),(2,6),(3,5),(4,2),(4,5),(5,6),(6,1)],7)             => 0
([(0,3),(0,4),(1,5),(2,5),(3,6),(4,2),(4,6),(6,1)],7)             => 0
([(0,4),(0,5),(1,6),(2,6),(3,6),(4,3),(5,1),(5,2)],7)             => 1
([(0,3),(0,4),(1,6),(2,6),(3,5),(4,1),(4,2),(4,5),(5,6)],7)       => 0
([(0,5),(1,6),(2,6),(3,4),(4,2),(5,1),(5,3)],7)                   => 0
([(0,3),(0,4),(1,6),(2,5),(3,5),(4,1),(4,2),(5,6)],7)             => 0
([(0,5),(1,6),(2,6),(4,2),(5,1),(5,4),(6,3)],7)                   => 0
([(0,4),(0,5),(1,6),(2,6),(4,6),(5,1),(5,2),(6,3)],7)             => 0
([(0,3),(0,4),(1,6),(2,6),(3,2),(3,5),(4,1),(4,5),(5,6)],7)       => 0
([(0,3),(0,4),(1,6),(2,5),(3,2),(4,1),(4,5),(5,6)],7)             => 0
([(0,2),(0,5),(1,6),(2,6),(3,4),(4,1),(5,3)],7)                   => 1
([(0,4),(1,6),(2,6),(3,5),(4,3),(5,1),(5,2)],7)                   => 0
([(0,2),(0,3),(0,4),(1,5),(2,6),(3,5),(4,1),(5,6)],7)             => 1
([(0,3),(0,5),(2,6),(3,6),(4,1),(5,2),(6,4)],7)                   => 0
([(0,4),(0,5),(1,6),(2,6),(3,2),(4,3),(5,1)],7)                   => 1
([(0,4),(1,6),(2,6),(3,2),(4,5),(5,1),(5,3)],7)                   => 0
([(0,2),(0,4),(1,6),(2,5),(3,1),(3,5),(4,3),(5,6)],7)             => 0
([(0,6),(2,3),(3,5),(4,2),(5,1),(6,4)],7)                         => 0
([(0,4),(0,5),(1,6),(2,6),(4,2),(5,1),(6,3)],7)                   => 0
([(0,3),(0,5),(1,6),(3,6),(4,1),(5,4),(6,2)],7)                   => 0
([(0,4),(1,6),(2,6),(4,5),(5,1),(5,2),(6,3)],7)                   => 0

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Created: Oct 01, 2020 at 09:22 by Henri Mühle

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Last Updated: Feb 08, 2021 at 23:23 by Martin Rubey