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A023213
Primes p such that 4p + 3 is prime.
14
2, 5, 7, 11, 17, 19, 31, 37, 41, 47, 59, 67, 89, 107, 109, 149, 151, 157, 179, 181, 227, 229, 241, 257, 271, 307, 331, 349, 359, 367, 389, 401, 439, 457, 461, 467, 487, 499, 509, 521, 571, 577, 587, 599, 647, 661, 677, 691, 719, 769, 797, 829, 839, 877, 881, 907, 929, 941
OFFSET
1,1
LINKS
MATHEMATICA
Select[Prime@Range@500, PrimeQ[4 # + 3] &] (* Vincenzo Librandi, May 19 2014 *)
PROG
(Magma) [ n: n in PrimesUpTo(1000) | IsPrime(4*n+3) ]; // Vincenzo Librandi, Nov 20 2010
(PARI) select(p->isprime(4*p+3), primes(100)) \\ Charles R Greathouse IV, Mar 21 2013
CROSSREFS
Cf. A007700.
Sequence in context: A023207 A038611 A265761 * A162575 A066408 A142352
KEYWORD
nonn,easy
STATUS
approved