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

 

Logo

Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing.
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A217071 Numbers n such that (n^17-1)/(n-1) is prime. 9
2, 11, 20, 21, 28, 31, 55, 57, 62, 84, 87, 97, 107, 109, 129, 147, 149, 157, 160, 170, 181, 189, 191, 207, 241, 247, 251, 274, 295, 297, 315, 327, 335, 349, 351, 355, 364, 365, 368, 379, 383, 410, 419, 423, 431, 436, 438, 466, 472, 506, 513, 527, 557, 571, 597 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

MATHEMATICA

Select[Range[2, 1000], PrimeQ[(#^17 - 1)/(# - 1)] &] (* T. D. Noe, Sep 26 2012 *)

PROG

(MAGMA) [n: n in [2..1000] |IsPrime((n^17 - 1) div (n - 1))]; // Vincenzo Librandi, Sep 28 2012

(PARI) is(n)=isprime((n^17-1)/(n-1)) \\ Charles R Greathouse IV, Feb 17 2017

CROSSREFS

Cf. A002384, A049409, A100330, A162862, A217070-A217089.

Sequence in context: A105076 A103200 A067670 * A159879 A017185 A279774

Adjacent sequences:  A217068 A217069 A217070 * A217072 A217073 A217074

KEYWORD

nonn,easy

AUTHOR

Tim Johannes Ohrtmann, Sep 26 2012

EXTENSIONS

More terms from T. D. Noe, Sep 26 2012

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 December 5 22:37 EST 2019. Contains 329782 sequences. (Running on oeis4.)