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Statistic identifier: St001758

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Collection: Graphs

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Description: The number of orbits of promotion on a graph.

Let $(V, E)$ be a graph with $n=|V|$ vertices, and let $\sigma: V \to [n]$ be a labelling of its vertices.  Let 
$
\tau_{i, j}(\sigma) = 
\begin{cases}
\sigma & \text{if $\{\sigma^{-1}(i), \sigma^{-1}(j)\}\in E$}\\
(i, j)\circ\sigma & \text{otherwise}.
\end{cases}
$

The promotion operator is the product $\tau_{n-1,n}\dots\tau_{1,2}$.

This statistic records the number of orbits in the orbit decomposition of promotion.

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References: [1]   Defant, C. Toric Promotion [[arXiv:2112.06843]]

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Code:
from sage.combinat.cyclic_sieving_phenomenon import orbit_decomposition
def toggle_labelling(G, pi, i, j):
    if G.has_edge(pi.index(i), pi.index(j)):
        return pi
    sigma = [j if e == i else i if e == j else e for e in pi]
    return Permutation(sigma)

def promotion_labelling(G, pi):
    n = G.num_verts()
    assert set(G.vertices()) == set(range(n))
    for i in range(1, n):
        pi = toggle_labelling(G, pi, i, i+1)
    return pi

def promotion_labelling_orbits(G):
    G = G.canonical_label().copy(immutable=True)
    return promotion_labelling_orbits_aux(G)

@cached_function
def promotion_labelling_orbits_aux(G):
    n = G.num_verts()
    return orbit_decomposition(Permutations(n),
                               lambda pi: promotion_labelling(G, pi))

def statistic(G):
    return len(promotion_labelling_orbits(G))

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

([],1)                                                                                          => 1
([],2)                                                                                          => 1
([(0,1)],2)                                                                                     => 2
([],3)                                                                                          => 2
([(1,2)],3)                                                                                     => 2
([(0,2),(1,2)],3)                                                                               => 4
([(0,1),(0,2),(1,2)],3)                                                                         => 6
([],4)                                                                                          => 6
([(2,3)],4)                                                                                     => 6
([(1,3),(2,3)],4)                                                                               => 4
([(0,3),(1,3),(2,3)],4)                                                                         => 10
([(0,3),(1,2)],4)                                                                               => 8
([(0,3),(1,2),(2,3)],4)                                                                         => 10
([(1,2),(1,3),(2,3)],4)                                                                         => 6
([(0,3),(1,2),(1,3),(2,3)],4)                                                                   => 12
([(0,2),(0,3),(1,2),(1,3)],4)                                                                   => 16
([(0,2),(0,3),(1,2),(1,3),(2,3)],4)                                                             => 18
([(0,1),(0,2),(0,3),(1,2),(1,3),(2,3)],4)                                                       => 24
([],5)                                                                                          => 24
([(3,4)],5)                                                                                     => 24
([(2,4),(3,4)],5)                                                                               => 16
([(1,4),(2,4),(3,4)],5)                                                                         => 16
([(0,4),(1,4),(2,4),(3,4)],5)                                                                   => 40
([(1,4),(2,3)],5)                                                                               => 24
([(1,4),(2,3),(3,4)],5)                                                                         => 12
([(0,1),(2,4),(3,4)],5)                                                                         => 16
([(2,3),(2,4),(3,4)],5)                                                                         => 24
([(0,4),(1,4),(2,3),(3,4)],5)                                                                   => 24
([(1,4),(2,3),(2,4),(3,4)],5)                                                                   => 16
([(0,4),(1,4),(2,3),(2,4),(3,4)],5)                                                             => 40
([(1,3),(1,4),(2,3),(2,4)],5)                                                                   => 24
([(0,4),(1,2),(1,3),(2,4),(3,4)],5)                                                             => 32
([(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                                             => 24
([(0,4),(1,3),(2,3),(2,4),(3,4)],5)                                                             => 28
([(0,4),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                                       => 40
([(0,3),(0,4),(1,3),(1,4),(2,3),(2,4)],5)                                                       => 56
([(0,3),(0,4),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                                 => 60
([(0,4),(1,3),(2,3),(2,4)],5)                                                                   => 28
([(0,1),(2,3),(2,4),(3,4)],5)                                                                   => 24
([(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)                                                       => 48
([(0,3),(0,4),(1,2),(1,4),(2,3)],5)                                                             => 40
([(0,1),(0,4),(1,3),(2,3),(2,4),(3,4)],5)                                                       => 48
([(0,3),(0,4),(1,2),(1,4),(2,3),(2,4),(3,4)],5)                                                 => 60
([(0,4),(1,2),(1,3),(2,3),(2,4),(3,4)],5)                                                       => 40
([(1,2),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                                       => 24
([(0,4),(1,2),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                                 => 48
([(0,3),(0,4),(1,2),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                           => 72
([(0,3),(0,4),(1,2),(1,3),(1,4),(2,3),(2,4)],5)                                                 => 64
([(0,2),(0,3),(0,4),(1,2),(1,3),(1,4),(2,4),(3,4)],5)                                           => 84
([(0,2),(0,3),(0,4),(1,2),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                                     => 96
([(0,1),(0,2),(0,3),(0,4),(1,2),(1,3),(1,4),(2,3),(2,4),(3,4)],5)                               => 120
([],6)                                                                                          => 120
([(4,5)],6)                                                                                     => 120
([(3,5),(4,5)],6)                                                                               => 80
([(2,5),(3,5),(4,5)],6)                                                                         => 80
([(1,5),(2,5),(3,5),(4,5)],6)                                                                   => 40
([(0,5),(1,5),(2,5),(3,5),(4,5)],6)                                                             => 148
([(2,5),(3,4)],6)                                                                               => 120
([(2,5),(3,4),(4,5)],6)                                                                         => 60
([(1,2),(3,5),(4,5)],6)                                                                         => 80
([(3,4),(3,5),(4,5)],6)                                                                         => 120
([(1,5),(2,5),(3,4),(4,5)],6)                                                                   => 32
([(0,1),(2,5),(3,5),(4,5)],6)                                                                   => 96
([(2,5),(3,4),(3,5),(4,5)],6)                                                                   => 80
([(0,5),(1,5),(2,5),(3,4),(4,5)],6)                                                             => 112
([(1,5),(2,5),(3,4),(3,5),(4,5)],6)                                                             => 40
([(0,5),(1,5),(2,5),(3,4),(3,5),(4,5)],6)                                                       => 152
([(2,4),(2,5),(3,4),(3,5)],6)                                                                   => 120
([(0,5),(1,5),(2,4),(3,4)],6)                                                                   => 80
([(1,5),(2,3),(2,4),(3,5),(4,5)],6)                                                             => 32
([(0,5),(1,5),(2,3),(3,4),(4,5)],6)                                                             => 96
([(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                             => 120
([(1,5),(2,4),(3,4),(3,5),(4,5)],6)                                                             => 28
([(0,5),(1,5),(2,4),(3,4),(4,5)],6)                                                             => 96
([(0,5),(1,5),(2,3),(2,4),(3,5),(4,5)],6)                                                       => 128
([(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                       => 40
([(0,5),(1,5),(2,4),(3,4),(3,5),(4,5)],6)                                                       => 108
([(0,5),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 140
([(1,4),(1,5),(2,4),(2,5),(3,4),(3,5)],6)                                                       => 56
([(0,5),(1,4),(2,4),(2,5),(3,4),(3,5)],6)                                                       => 116
([(0,5),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5)],6)                                                 => 156
([(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 60
([(0,5),(1,4),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 120
([(0,5),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 164
([(0,4),(0,5),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5)],6)                                           => 260
([(0,4),(0,5),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 276
([(0,5),(1,4),(2,3)],6)                                                                         => 128
([(1,5),(2,4),(3,4),(3,5)],6)                                                                   => 44
([(0,1),(2,5),(3,4),(4,5)],6)                                                                   => 72
([(1,2),(3,4),(3,5),(4,5)],6)                                                                   => 120
([(0,5),(1,4),(2,3),(3,5),(4,5)],6)                                                             => 92
([(1,4),(2,3),(2,5),(3,5),(4,5)],6)                                                             => 48
([(0,1),(2,5),(3,4),(3,5),(4,5)],6)                                                             => 96
([(0,4),(1,5),(2,3),(2,5),(3,5),(4,5)],6)                                                       => 120
([(1,4),(1,5),(2,3),(2,5),(3,5),(4,5)],6)                                                       => 48
([(0,5),(1,4),(1,5),(2,3),(2,5),(3,5),(4,5)],6)                                                 => 160
([(1,4),(1,5),(2,3),(2,5),(3,4)],6)                                                             => 80
([(0,5),(1,4),(2,3),(2,4),(3,5),(4,5)],6)                                                       => 116
([(1,2),(1,5),(2,4),(3,4),(3,5),(4,5)],6)                                                       => 56
([(0,5),(1,2),(1,4),(2,3),(3,5),(4,5)],6)                                                       => 104
([(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                                                       => 40
([(0,5),(1,4),(2,3),(3,4),(3,5),(4,5)],6)                                                       => 72
([(0,5),(1,2),(1,5),(2,4),(3,4),(3,5),(4,5)],6)                                                 => 136
([(0,5),(1,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 116
([(1,4),(1,5),(2,3),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 60
([(0,5),(1,4),(1,5),(2,3),(2,5),(3,4),(3,5),(4,5)],6)                                           => 152
([(0,5),(1,4),(2,3),(2,4),(3,5)],6)                                                             => 100
([(0,1),(2,4),(2,5),(3,4),(3,5)],6)                                                             => 144
([(0,5),(1,5),(2,3),(2,4),(3,4)],6)                                                             => 96
([(0,4),(1,2),(1,3),(2,5),(3,5),(4,5)],6)                                                       => 124
([(0,4),(1,2),(1,5),(2,5),(3,4),(3,5)],6)                                                       => 112
([(0,4),(1,2),(2,5),(3,4),(3,5),(4,5)],6)                                                       => 108
([(0,1),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                       => 144
([(0,4),(1,4),(2,3),(2,5),(3,5),(4,5)],6)                                                       => 112
([(0,3),(0,4),(1,2),(1,5),(2,5),(3,5),(4,5)],6)                                                 => 144
([(0,3),(1,4),(1,5),(2,4),(2,5),(3,5),(4,5)],6)                                                 => 144
([(0,4),(1,2),(1,5),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 120
([(0,1),(0,5),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 152
([(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                       => 120
([(0,5),(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                                                 => 144
([(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 48
([(0,5),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 168
([(0,1),(0,5),(1,4),(2,4),(2,5),(3,4),(3,5)],6)                                                 => 156
([(0,3),(0,5),(1,3),(1,5),(2,4),(2,5),(3,4),(4,5)],6)                                           => 196
([(0,3),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 168
([(0,5),(1,4),(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                                           => 148
([(0,1),(0,5),(1,4),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 196
([(0,4),(0,5),(1,4),(1,5),(2,3),(2,5),(3,4),(3,5),(4,5)],6)                                     => 216
([(0,5),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                                           => 168
([(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 72
([(0,5),(1,4),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 136
([(0,5),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 176
([(0,4),(0,5),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                                     => 272
([(0,4),(0,5),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 288
([(0,5),(1,3),(1,4),(2,3),(2,4),(3,5),(4,5)],6)                                                 => 160
([(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                                                 => 64
([(0,5),(1,3),(1,4),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                                           => 172
([(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                                           => 84
([(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                                     => 200
([(0,4),(0,5),(1,2),(1,3),(2,5),(3,4)],6)                                                       => 140
([(0,3),(0,5),(1,2),(1,5),(2,4),(3,4),(4,5)],6)                                                 => 180
([(0,5),(1,2),(1,4),(2,3),(3,4),(3,5),(4,5)],6)                                                 => 144
([(0,1),(0,2),(1,5),(2,4),(3,4),(3,5),(4,5)],6)                                                 => 156
([(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)                                                 => 136
([(0,1),(0,5),(1,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 196
([(0,4),(1,3),(1,5),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                                           => 160
([(0,4),(0,5),(1,3),(1,5),(2,3),(2,4),(3,5),(4,5)],6)                                           => 184
([(0,4),(0,5),(1,3),(1,5),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                                     => 208
([(0,4),(0,5),(1,2),(1,3),(2,4),(2,5),(3,4),(3,5)],6)                                           => 224
([(0,5),(1,2),(1,3),(1,4),(2,3),(2,4),(3,5),(4,5)],6)                                           => 176
([(0,4),(0,5),(1,2),(1,3),(1,5),(2,4),(2,5),(3,4),(3,5)],6)                                     => 256
([(0,4),(0,5),(1,2),(1,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 240
([(0,4),(0,5),(1,2),(1,3),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 272
([(0,5),(1,2),(1,3),(1,4),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 192
([(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 96
([(0,5),(1,3),(1,4),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 184
([(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 216
([(0,4),(0,5),(1,2),(1,4),(2,3),(2,5),(3,4),(3,5),(4,5)],6)                                     => 224
([(0,4),(0,5),(1,3),(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                                     => 192
([(0,4),(0,5),(1,3),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 240
([(0,4),(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                         => 312
([(0,3),(0,4),(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5)],6)                                     => 336
([(0,1),(0,2),(0,3),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 352
([(0,4),(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                               => 296
([(0,3),(0,4),(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,5),(4,5)],6)                         => 384
([(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)                   => 408
([(0,4),(0,5),(1,2),(1,3),(2,3),(4,5)],6)                                                       => 144
([(0,2),(1,4),(1,5),(2,3),(3,4),(3,5),(4,5)],6)                                                 => 136
([(0,1),(0,5),(1,5),(2,3),(2,4),(3,4),(4,5)],6)                                                 => 144
([(0,1),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                                 => 144
([(0,1),(0,5),(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                                           => 168
([(0,1),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                           => 168
([(0,1),(0,5),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 192
([(0,4),(0,5),(1,2),(1,3),(2,3),(2,5),(3,4),(4,5)],6)                                           => 188
([(0,4),(0,5),(1,2),(1,3),(1,4),(2,3),(2,5),(3,5),(4,5)],6)                                     => 232
([(0,3),(1,2),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 192
([(0,3),(0,5),(1,2),(1,4),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 212
([(0,1),(0,5),(1,4),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                                     => 232
([(0,3),(0,5),(1,2),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 256
([(0,3),(0,4),(0,5),(1,2),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5)],6)                               => 312
([(0,3),(0,4),(0,5),(1,2),(1,4),(1,5),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                         => 336
([(0,4),(0,5),(1,3),(1,5),(2,3),(2,4),(2,5),(3,4)],6)                                           => 200
([(0,1),(0,5),(1,4),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                                           => 184
([(0,3),(0,4),(1,2),(1,4),(1,5),(2,3),(2,5),(3,5),(4,5)],6)                                     => 240
([(0,3),(0,4),(0,5),(1,2),(1,4),(1,5),(2,3),(2,5),(3,5),(4,5)],6)                               => 280
([(0,3),(0,4),(0,5),(1,2),(1,4),(1,5),(2,3),(2,5),(3,4)],6)                                     => 264
([(0,1),(0,3),(0,5),(1,2),(1,4),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 308
([(0,4),(0,5),(1,2),(1,3),(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                               => 264
([(0,1),(0,4),(0,5),(1,3),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                         => 344
([(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)                   => 408
([(0,2),(0,5),(1,3),(1,4),(1,5),(2,3),(2,4),(3,4),(3,5),(4,5)],6)                               => 288
([(0,4),(0,5),(1,2),(1,3),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 264
([(0,4),(0,5),(1,2),(1,3),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                         => 312
([(0,5),(1,2),(1,3),(1,4),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 216
([(1,2),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                               => 120
([(0,5),(1,2),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                         => 240
([(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)                   => 360
([(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)             => 480
([(0,3),(0,4),(0,5),(1,2),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                         => 368
([(0,4),(0,5),(1,2),(1,3),(1,4),(1,5),(2,3),(2,4),(2,5),(3,4),(3,5)],6)                         => 336
([(0,1),(0,4),(0,5),(1,2),(1,3),(2,3),(2,4),(2,5),(3,4),(3,5),(4,5)],6)                         => 384
([(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)                   => 432
([(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)                   => 480
([(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)             => 528
([(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)       => 600
([(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) => 720

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Created: Dec 14, 2021 at 16:03 by Martin Rubey

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Last Updated: Dec 14, 2021 at 16:03 by Martin Rubey