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A217073 Numbers n such that (n^23-1)/(n-1) is prime. 7
10, 40, 82, 113, 127, 141, 170, 257, 275, 287, 295, 315, 344, 373, 442, 468, 609, 634, 646, 663, 671, 710, 819, 834, 857, 884, 894, 904, 992, 997, 1060, 1069, 1077, 1120, 1143, 1190, 1232, 1253, 1261, 1280, 1291, 1347, 1407, 1436, 1448, 1483, 1514, 1570, 1642 (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, 1700], PrimeQ[(#^23 - 1)/(# - 1)] &] (* T. D. Noe, Sep 26 2012 *)

PROG

(MAGMA) [n: n in [2..1700] |IsPrime((n^23 - 1) div (n - 1))]; // Vincenzo Librandi, Sep 28 2012

(PARI) is(n)=isprime((n^23-1)/(n-1)) \\ Charles R Greathouse IV, Feb 17 2017

CROSSREFS

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

Sequence in context: A328093 A306830 A305131 * A210376 A060317 A033583

Adjacent sequences:  A217070 A217071 A217072 * A217074 A217075 A217076

KEYWORD

nonn,easy

AUTHOR

Tim Johannes Ohrtmann, Sep 26 2012

EXTENSIONS

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

STATUS

approved

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Last modified December 5 20:45 EST 2019. Contains 329779 sequences. (Running on oeis4.)