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Statistic identifier: St001952

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Collection: Finite Cartan types

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Description: The number of conjugacy classes in the Weyl group of finite Cartan type whose elements are involutions.

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References: 

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Code:
def statistic(ct):
    return sum(1 for w in WeylGroup(ct).conjugacy_classes_representatives() if w.order() == 2)

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Statistic values:

['A',1] => 1
['A',2] => 1
['B',2] => 3
['G',2] => 3
['A',3] => 2
['B',3] => 5
['C',3] => 5
['A',4] => 2
['B',4] => 8
['C',4] => 8
['D',4] => 6
['F',4] => 7
['A',5] => 3
['B',5] => 11
['C',5] => 11
['D',5] => 5
['A',6] => 3
['B',6] => 15
['C',6] => 15
['D',6] => 10
['E',6] => 4
['A',7] => 4
['B',7] => 19
['C',7] => 19
['D',7] => 9
['E',7] => 9
['A',8] => 4
['B',8] => 24
['C',8] => 24
['D',8] => 15
['E',8] => 9

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Created: Jul 09, 2024 at 12:00 by Martin Rubey

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Last Updated: Jul 09, 2024 at 12:00 by Martin Rubey