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 A173295 Primes of the form n^2+n+1 or n^2+n+9. 0
 3, 7, 11, 13, 29, 31, 43, 73, 157, 191, 211, 241, 281, 307, 389, 421, 463, 601, 659, 757, 821, 1123, 1483, 1723, 1901, 2459, 2551, 2971, 3089, 3307, 3541, 3907, 4423, 4831, 5113, 5701, 5861, 6007, 6163, 6329, 6481, 7841, 8011, 8191, 9901, 10303, 11131 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE a(1)=3 because 1^2+1+1=3 is prime, a(3)=11 because 1^2+1+9=11 is prime. MATHEMATICA Union[Select[Flatten[Table[n^2+n+{1, 9}, {n, 200}]], PrimeQ]] (* Harvey P. Dale, Aug 28 2012 *) CROSSREFS Cf. A002378, A173288. Sequence in context: A111363 A193258 A114273 * A191040 A074336 A086475 Adjacent sequences:  A173292 A173293 A173294 * A173296 A173297 A173298 KEYWORD nonn AUTHOR Juri-Stepan Gerasimov, Feb 15 2010 EXTENSIONS Added 3, removed 133, replaced 607 by 601 - R. J. Mathar, Feb 24 2010 STATUS approved

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Last modified December 14 04:53 EST 2018. Contains 318090 sequences. (Running on oeis4.)