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A173641 Primes p such that p^2+4 and p^2-6 are both prime. 2
3, 5, 7, 13, 17, 47, 67, 73, 97, 167, 193, 293, 317, 373, 463, 487, 503, 593, 607, 677, 787, 823, 827, 1087, 1613, 1637, 1987, 2477, 2543, 2687, 2777, 2833, 2903, 2957, 3023, 3583, 3593, 3917, 4093 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
p^2+4 and p^2-6 are both primes if a(n)^2+4 is in the sequence A172240 such that A172240(n) - 10 is also prime.
LINKS
MATHEMATICA
Select[Prime[Range[800]], PrimeQ[#^2 + 4]&& PrimeQ[#^2 - 6]&] (* Vincenzo Librandi, Apr 16 2013 *)
PROG
(Sage) A173641 = list(p for p in primes(10^5) if is_prime(p^2+4) and is_prime(p^2-6))
(Magma) [p: p in PrimesUpTo(4100) | IsPrime(p^2+4)and IsPrime(p^2-6)]; // Vincenzo Librandi, Apr 16 2013
CROSSREFS
Sequence in context: A194829 A226794 A300748 * A153645 A106878 A192294
KEYWORD
nonn,easy
AUTHOR
Giovanni Teofilatto, Nov 24 2010
EXTENSIONS
Corrected and extended by D. S. McNeil, Nov 24 2010
STATUS
approved

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Last modified March 28 07:20 EDT 2024. Contains 371235 sequences. (Running on oeis4.)