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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

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

Cf. A000040, A027757.

Subsequence of A002476.

Sequence in context: A106904 A106903 A098413 * A103176 A156940 A220162

Adjacent sequences:  A174149 A174150 A174151 * A174153 A174154 A174155

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, Mar 10 2010

STATUS

approved

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Last modified January 28 09:17 EST 2020. Contains 331318 sequences. (Running on oeis4.)