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A174152
Primes p such that p^2+p+9 is also prime.
1
13, 19, 43, 79, 139, 151, 211, 271, 373, 433, 523, 643, 739, 751, 769, 853, 919, 1033, 1051, 1093, 1129, 1171, 1423, 1429, 1471, 1531, 1579, 1663, 1741, 1759, 1789, 1933, 2053, 2281, 2389, 2521, 2689, 2731, 2749, 2833, 3061, 3109, 3163, 3271, 3313, 3319
OFFSET
1,1
LINKS
FORMULA
A027757 INTERSECT A000040. [From R. J. Mathar, Jul 06 2010]
EXAMPLE
For p=13, 13^2+13+9=191; p=19, 19^2+19+9=389; p=43, 43^2+43+9=1901.
MATHEMATICA
Select[Prime[Range[500]], PrimeQ[#^2 + # + 9]&] (* Vincenzo Librandi, Apr 16 2013 *)
PROG
(Magma) [p: p in PrimesUpTo(10000) | IsPrime(p^2+p+9)];
CROSSREFS
Subsequence of A002476.
Sequence in context: A106904 A106903 A098413 * A103176 A156940 A220162
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Mar 10 2010
STATUS
approved