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A111001
Numbers n such that 23*n^2 - 25 is prime.
0
2, 8, 14, 48, 54, 56, 58, 78, 84, 92, 96, 106, 128, 142, 154, 156, 174, 184, 212, 222, 238, 252, 272, 282, 288, 342, 362, 366, 372, 378, 398, 418, 436, 448, 454, 464, 474, 488, 496, 516, 518, 524, 526, 532, 546, 554, 574, 594, 604, 618, 624, 638, 656, 664, 702
OFFSET
1,1
EXAMPLE
If n=92 then (23*n^2) - 25 = 194647 (prime).
MATHEMATICA
Select[Range[1000], PrimeQ[23#^2-25]&] (* Harvey P. Dale, Jun 10 2014 *)
PROG
(Magma) [n: n in [2..100000] |IsPrime((23*n^2)-25)]; // Vincenzo Librandi, Nov 13 2010
(PARI) is(n)=isprime(23*n^2-25) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Sequence in context: A333053 A333054 A119752 * A055258 A277649 A192777
KEYWORD
nonn,easy,changed
AUTHOR
Parthasarathy Nambi, Sep 30 2005
STATUS
approved