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A364921
Number of conjugacy classes of subgroups of the group GL(2, Z_n) of invertible 2 X 2 matrices mod n.
0
1, 4, 16, 62, 48, 109, 84, 2265, 324, 345, 114, 5359, 217, 636, 2540, 27908, 218, 2872, 272, 20933, 4089, 756, 169, 780487, 892, 1813, 3015, 30562, 349, 31419, 510, 191856, 5096, 1743, 14139, 115902, 685, 2156, 13191, 3764246, 662, 51063, 600, 38346, 56222, 1130, 271
OFFSET
1,2
PROG
(Magma) [#Subgroups(GL(2, ResidueClassRing(n))) : n in [2..50]];
(Sage) [len(GL(2, Zmod(n)).as_permutation_group().conjugacy_classes_subgroups()) for n in range(2, 50)]
CROSSREFS
Sequence in context: A283858 A283409 A192468 * A365835 A365860 A276042
KEYWORD
nonn
AUTHOR
Robin Visser, Aug 12 2023
STATUS
approved