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A188549 Numbers n such that 8*n^2+1 is a prime. 2
3, 12, 15, 18, 21, 33, 36, 48, 51, 66, 78, 81, 93, 102, 114, 120, 132, 150, 153, 162, 180, 183, 213, 225, 228, 231, 234, 237, 243, 246, 252, 279, 282, 285, 294, 303, 318, 324, 333, 375, 378, 381, 384, 393, 396, 399, 417, 432, 450, 459, 468, 480, 489, 495, 510 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Half of the even terms of A089001. - R. J. Mathar, Apr 09 2011

LINKS

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

MATHEMATICA

Select[Range[600], PrimeQ[8#^2+1]&] (* Harvey P. Dale, Apr 11 2012 *)

PROG

(Magma) [n: n in [1..1800]|IsPrime(8*n^2 + 1)]; - Vincenzo Librandi, 04 2011

CROSSREFS

Cf. A090685 (Primes of the form 8*n^2 + 1), A089001.

Sequence in context: A201273 A221920 A349663 * A287357 A044828 A248105

Adjacent sequences: A188546 A188547 A188548 * A188550 A188551 A188552

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, Apr 04 2011

STATUS

approved

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Last modified March 22 14:53 EDT 2023. Contains 361430 sequences. (Running on oeis4.)