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A360410 Number of passports of index n subgroups in PSL_2 (ZZ).

Original entry on oeis.org

1, 1, 2, 2, 1, 8, 4, 5, 12, 12, 7, 48, 24, 35, 75, 80, 37, 269, 114, 193, 404, 359, 174, 1357, 519, 722, 1664, 1784, 776, 4995, 2054
Offset: 1

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Author

David Berghaus, Feb 06 2023

Keywords

Comments

The passports are defined as the conjugacy classes of index n subgroups in PSL_2 (ZZ) modulo the ramification degrees of the covering maps and the monodromy groups.

Links

Crossrefs

Cf. A121350, A005133.

Extensions

Corrected by David Berghaus, Sep 02 2023

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