login
A015931
Positive integers n such that 2^n (mod n) == 2^9 (mod n).
10
1, 2, 3, 4, 5, 8, 9, 16, 17, 21, 27, 32, 45, 63, 64, 99, 105, 117, 124, 128, 153, 171, 189, 207, 254, 256, 261, 273, 279, 333, 369, 387, 423, 429, 477, 512, 513, 531, 549, 585, 603, 639, 657, 711, 747, 801, 873, 909, 927, 945, 963, 981, 1017, 1143, 1179, 1197, 1209, 1233, 1251, 1341, 1359, 1365, 1413, 1467, 1472, 1503, 1504, 1557, 1611, 1629, 1665, 1719, 1737, 1773, 1785, 1791, 1899, 1971
OFFSET
1,2
COMMENTS
For all m, 2^A128123(m)-1 belongs to this sequence.
LINKS
OEIS Wiki, 2^n mod n
MATHEMATICA
Select[Range[2000], PowerMod[2, 9, #]==PowerMod[2, #, #]&] (* Harvey P. Dale, Apr 01 2017 *)
PROG
(PARI) isok(n) = Mod(2, n)^n == 2^9; \\ Michel Marcus, Sep 23 2016
CROSSREFS
Contains A208157 as a subsequence.
The odd terms form A276970.
Sequence in context: A369294 A287117 A286431 * A330400 A306044 A263581
KEYWORD
nonn
EXTENSIONS
Edited by Max Alekseyev, Jul 30 2011
Definition clarified by Harvey P. Dale, Apr 01 2017
STATUS
approved