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A023216
Primes p such that 4*p + 9 is also prime.
4
2, 5, 7, 11, 13, 23, 37, 41, 43, 47, 67, 71, 97, 103, 113, 137, 151, 163, 167, 173, 181, 191, 197, 211, 233, 251, 263, 271, 277, 293, 307, 317, 397, 401, 421, 431, 433, 463, 467, 491, 557, 571, 587, 593, 607, 617, 653, 683, 727, 757, 811, 823, 863, 877, 881, 883, 887, 907
OFFSET
1,1
LINKS
MATHEMATICA
Select[Prime[Range[2000]], PrimeQ[4# + 9]&] (* Vincenzo Librandi, Feb 02 2014 *)
PROG
(Magma) [n: n in [0..1000] | IsPrime(n) and IsPrime(4*n+9)]; // Vincenzo Librandi, Nov 19 2010
CROSSREFS
Sequence in context: A256396 A291280 A120330 * A079449 A236071 A038885
KEYWORD
nonn,easy
STATUS
approved