A316498 Number of normal subgroups of the special linear group SL(2, Z_n).

1, 3, 4, 7, 3, 13, 3, 15, 6, 10, 3, 32, 3, 10, 13, 26, 3, 20, 3, 25, 13, 10, 3, 75, 5, 10, 8, 25, 3, 48, 3, 37, 13, 10, 10, 50, 3, 10, 13, 60, 3, 48, 3, 25, 20, 10, 3, 135, 5, 17, 13, 25, 3, 27, 10, 60, 13, 10, 3, 127, 3, 10, 20, 48, 10, 48, 3, 25, 13, 38

Offset

1,2

Links

Table of n, a(n) for n=1..70.

Prog

(GAP) Concatenation([1], List([2..20], n->Size(NormalSubgroups(SL(2, Integers mod n)))));

Crossrefs

Cf. A000056, A066541.

Sequence in context: A082089 A089961 A359954 * A200681 A161775 A282535

Adjacent sequences: A316495 A316496 A316497 * A316499 A316500 A316501

Keyword

nonn

Author

Andrew Howroyd, Jul 04 2018

Status

approved