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 A171831 Primes p such that p and 3*p^2+3*p-1 are both prime. 3
 2, 5, 7, 29, 37, 79, 89, 97, 107, 109, 127, 139, 149, 197, 229, 239, 277, 317, 379, 397, 487, 499, 509, 557, 587, 599, 607, 757, 769, 887, 907, 1019, 1049, 1069, 1097, 1297, 1307, 1439, 1499, 1559, 1567, 1609, 1619, 1637, 1667, 1709, 1759, 1847, 1979, 1997 (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[Prime[Range[500]], PrimeQ[3#^2+3#-1]&] (* Harvey P. Dale, Jul 24 2011 *) PROG (MAGMA) [p: p in PrimesUpTo(2000) | IsPrime(3*p^2+3*p-1)]; // Vincenzo Librandi, Dec 31 2013 CROSSREFS Sequence in context: A002317 A137098 A082013 * A192560 A174288 A293062 Adjacent sequences:  A171828 A171829 A171830 * A171832 A171833 A171834 KEYWORD nonn,easy AUTHOR Vincenzo Librandi, Dec 19 2009 STATUS approved

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Last modified December 1 20:39 EST 2020. Contains 338854 sequences. (Running on oeis4.)