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A028876
Numbers k such that k^2 - 5 is prime.
5
4, 6, 8, 12, 14, 16, 22, 24, 32, 34, 36, 38, 42, 44, 46, 52, 58, 64, 72, 74, 78, 82, 94, 102, 112, 116, 122, 132, 144, 152, 164, 166, 168, 174, 176, 182, 184, 186, 188, 198, 204, 212, 222, 226, 232, 234, 236, 252, 262, 264, 278, 284, 288, 292, 298, 302, 318, 324
OFFSET
1,1
LINKS
Eric Weisstein's World of Mathematics, Near-Square Prime
MATHEMATICA
Select[Range[400], PrimeQ[#^2 - 5] &] (* Alonso del Arte, Aug 27 2013 *)
PROG
(Magma) [n: n in [2..1000] |IsPrime(n^2 - 5 )]; // Vincenzo Librandi, Nov 18 2010
(PARI) is(n)=isprime(n^2-5) \\ Charles R Greathouse IV, Jun 06 2017
CROSSREFS
Sequence in context: A225508 A235036 A107303 * A271346 A053579 A074121
KEYWORD
nonn,easy
STATUS
approved