A174367 Primes p such that 2*p^4-+21 are also prime.

2, 197, 499, 587, 601, 1237, 2111, 2153, 2861, 3253, 3301, 3923, 4373, 5101, 5387, 5437, 6529, 6563, 7459, 9817, 9833, 10477, 11047, 11699, 12101, 12823, 12907, 13859, 14087, 15569, 21401, 21929, 22727, 23473, 23687, 23893, 25633, 26393

Offset

1,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Example

For p=2, 2*2^4-+21=(11,53); p=197, 2*197^4-+21=(3012276941,3012276983)

Mathematica

Select[Prime[Range[1000]], And@@PrimeQ[2 #^4 + {21, -21}]&] (* Vincenzo Librandi, Apr 10 2013 *)

Prog

(Magma) [p: p in PrimesUpTo(100000)|IsPrime(2*p^4-21) and IsPrime(2*p^4+21)];

Crossrefs

Sequence in context: A143659 A282700 A256410 * A262650 A123100 A033147

Adjacent sequences: A174364 A174365 A174366 * A174368 A174369 A174370

Keyword

nonn,easy

Author

Vincenzo Librandi, Mar 17 2010

Status

approved