A065501 - OEIS

A065501

Number of conjugacy classes in the group SL(2,Z_n) (see A000056).

1, 3, 7, 10, 9, 21, 11, 30, 25, 27, 15, 70, 17, 33, 63, 76, 21, 75, 23, 90, 77, 45, 27, 210, 49, 51, 79, 110, 33, 189, 35, 168, 105, 63, 99, 250, 41, 69, 119, 270, 45, 231, 47, 150, 225, 81, 51, 532, 81, 147, 147, 170, 57, 237, 135, 330, 161, 99, 63, 630, 65, 105, 275, 352, 153

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OFFSET

1,2

LINKS

Robin Visser, Table of n, a(n) for n = 1..500

FORMULA

For an odd prime p : a(p) = p + 4. - Robin Visser, Aug 06 2023

PROG

(Magma) [Nclasses(SpecialLinearGroup(2, ResidueClassRing(n))) : n in [2..50]]; // Robin Visser, Aug 06 2023

CROSSREFS

Cf. A062354, A000056, A000252

Sequence in context: A189244 A127789 A112105 * A144385 A144399 A310176