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A171832
Primes p such that p and 5*p^2+5*p-1 are both prime
4
2, 3, 5, 11, 29, 41, 47, 137, 197, 227, 251, 269, 293, 353, 359, 383, 401, 467, 641, 659, 701, 797, 839, 857, 929, 1103, 1163, 1193, 1229, 1259, 1289, 1319, 1373, 1439, 1451, 1487, 1523, 1553, 1559, 1721, 1787, 1847, 1871, 1877, 1889, 1913, 1949, 2081
OFFSET
1,1
LINKS
MATHEMATICA
Select[Prime[Range[400]], PrimeQ[5#^2+5#-1]&] (* Harvey P. Dale, Apr 03 2010 *)
PROG
(Magma) [p: p in PrimesUpTo(2500) | IsPrime(5*p^2+5*p-1)]; // Vincenzo Librandi, Aug 20 2014
(PARI) lista(nn) = {forprime(p=2, nn, if (isprime(5*p^2+5*p-1), print1(p, ", ")); ); } \\ Michel Marcus, Aug 20 2014
CROSSREFS
Sequence in context: A173758 A098642 A079447 * A084865 A047934 A090235
KEYWORD
nonn
AUTHOR
Vincenzo Librandi, Dec 19 2009
EXTENSIONS
Corrected sequence because 1553 had been omitted Harvey P. Dale, Apr 03 2010
STATUS
approved