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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..55.

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

Adjacent sequences:  A110998 A110999 A111000 * A111002 A111003 A111004

KEYWORD

nonn,easy

AUTHOR

Parthasarathy Nambi, Sep 30 2005

STATUS

approved

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Last modified June 22 05:44 EDT 2021. Contains 345367 sequences. (Running on oeis4.)