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
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Mar 17 2010
STATUS
approved