A014951 Positive integers k such that k divides 12^k - 1.

1, 11, 121, 253, 1331, 2783, 5819, 11891, 14641, 30613, 64009, 130801, 133837, 161051, 273493, 336743, 558877, 704099, 768361, 849299, 1438811, 1472207, 1771561, 3008423, 3078251, 3544453, 3704173, 6147647, 6290339, 7745089

Offset

1,2

Comments

Also, the integers k such that k divides s(k), where s(1)=1 and s(j) = s(j-1) + j*12^(j-1).

From Alexander Adamchuk, May 16 2010: (Start)

11 divides a(n) for n > 1.

All powers of 11 are terms.

Prime divisors of a(n) in order of appearance: {11, 23, 47, 3037, 7019, 2663, 5171, 47917, 12973, ...}. (End)

Links

Seiichi Manyama, Table of n, a(n) for n = 1..100

Mathematica

Join[{1}, Select[Range[775*10^4], PowerMod[12, #, #]==1&]] (* Harvey P. Dale, Jun 08 2022 *)

Crossrefs

Cf. A015961.

Sequence in context: A045595 A228440 A015958 * A223223 A240942 A216131

Adjacent sequences: A014948 A014949 A014950 * A014952 A014953 A014954

Keyword

nonn

Author

Olivier Gérard

Extensions

a(11)-a(30) from Alexander Adamchuk, May 16 2010

Edited by Max Alekseyev, May 20 2011

Status

approved