login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A276970 Odd integers n such that 2^n == 2^9 (mod n). 7
1, 3, 5, 9, 17, 21, 27, 45, 63, 99, 105, 117, 153, 171, 189, 207, 261, 273, 279, 333, 369, 387, 423, 429, 477, 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, 1503, 1557, 1611, 1629, 1665, 1719, 1737 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Also, integers n such that 2^(n-9) == 1 (mod n).

Contains A208157 as a subsequence.

For all m, 2^A128123(m)-1 belongs to this sequence.

LINKS

Seiichi Manyama, Table of n, a(n) for n = 1..10000

MATHEMATICA

m = 2^9; Join[Select[Range[1, m, 2], Divisible[2^# - m, #] &], Select[Range[m + 1, 10^3, 2], PowerMod[2, #, #] == m &]] (* Robert Price, Oct 15 2018 *)

CROSSREFS

The odd terms of A015931.

Odd integers n such that 2^n == 2^k (mod n): A176997 (k=1), A173572 (k=2), A276967 (k=3), A033984 (k=4), A276968 (k=5), A215610 (k=6), A276969 (k=7), A215611 (k=8), this sequence (k=9), A215612 (k=10), A276971 (k=11), A215613 (k=12).

Sequence in context: A130114 A143106 A217099 * A294641 A143105 A032679

Adjacent sequences:  A276967 A276968 A276969 * A276971 A276972 A276973

KEYWORD

nonn,easy

AUTHOR

Max Alekseyev, Sep 22 2016

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 19 05:20 EDT 2019. Contains 324217 sequences. (Running on oeis4.)