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A172410
Numbers k such that 2k + 9 and 2k + 27 are prime.
1
1, 2, 5, 7, 10, 16, 17, 22, 26, 31, 35, 37, 40, 50, 52, 61, 65, 70, 77, 82, 85, 86, 92, 101, 107, 112, 115, 121, 127, 142, 152, 161, 170, 185, 187, 196, 206, 211, 215, 217, 220, 226, 241, 247, 257, 280, 295, 296, 302, 316, 317, 325, 332, 337, 341, 346, 350, 362, 365
OFFSET
1,2
LINKS
EXAMPLE
a(1)=1 because 2*1+9=11 and 2*1+27=29 are both prime.
MATHEMATICA
Select[Range[400], AllTrue[2#+{9, 27}, PrimeQ]&] (* Harvey P. Dale, Oct 06 2024 *)
PROG
(Magma) [n: n in [0..1000] |IsPrime(2*n+9) and IsPrime(2*n+27)]; // Vincenzo Librandi, Dec 06 2010
CROSSREFS
Sequence in context: A080180 A159942 A102339 * A266594 A103871 A068817
KEYWORD
nonn,easy,less
AUTHOR
EXTENSIONS
Corrected and extended by Vincenzo Librandi and Charles R Greathouse IV, Mar 24 2010
STATUS
approved