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Statistic identifier: St001155
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Collection: Finite Cartan types
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Description: The number of conjugacy classes of subgroups of the Weyl group of given type.
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References: [1] Number of permutation groups of degree n; also number of conjugacy classes of subgroups of symmetric group S_n; also number of molecular species of degree n. [[OEIS:A000638]]
[2] Number of conjugacy classes of subgroups of the hyperoctahedral group. [[OEIS:A269890]]
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Code:
def statistic(C):
return len(WeylGroup(C).as_permutation_group().conjugacy_classes_subgroups())
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Statistic values:
['A',1] => 2
['A',2] => 4
['B',2] => 8
['G',2] => 10
['A',3] => 11
['B',3] => 33
['C',3] => 33
['A',4] => 19
['B',4] => 193
['C',4] => 193
['D',4] => 98
['F',4] => 246
['A',5] => 56
['B',5] => 953
['C',5] => 953
['D',5] => 197
['A',6] => 96
['B',6] => 7440
['C',6] => 7440
['D',6] => 1916
['E',6] => 350
['A',7] => 296
['A',8] => 554
['A',9] => 1593
['A',10] => 3094
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Created: Apr 21, 2018 at 23:43 by Martin Rubey
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Last Updated: Oct 18, 2020 at 17:52 by Martin Rubey