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A217080 Numbers n such that (n^53-1)/(n-1) is prime. 6
24, 45, 60, 165, 235, 272, 285, 298, 307, 381, 416, 429, 623, 799, 858, 924, 929, 936, 1034, 1067, 1076, 1130, 1223, 1243, 1327, 1488, 1592, 1594, 1659, 1673, 1676, 1678, 1762, 1873, 1917, 1928, 1997, 2110, 2117, 2141, 2166, 2231, 2243, 2293, 2338, 2380, 2420 (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, 2500], PrimeQ[(#^53 - 1)/(# - 1)] &] (* T. D. Noe, Sep 26 2012 *)

PROG

(MAGMA) [n: n in [2..2450] |IsPrime((n^53 - 1) div (n - 1))]; // Vincenzo Librandi, Sep 28 2012

(PARI) is(n)=isprime((n^53-1)/(n-1)) \\ Charles R Greathouse IV, Feb 17 2017

CROSSREFS

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

Sequence in context: A211568 A324459 A324457 * A226327 A063323 A154590

Adjacent sequences:  A217077 A217078 A217079 * A217081 A217082 A217083

KEYWORD

nonn

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 May 14 19:53 EDT 2021. Contains 343903 sequences. (Running on oeis4.)