A071351 Numbers n such that both n^4 + 2 and n^4 - 2 are prime.

3, 21, 87, 99, 129, 141, 279, 627, 657, 777, 783, 795, 1653, 1725, 1833, 1959, 2001, 2043, 3039, 3399, 3609, 3861, 3975, 4257, 4371, 4491, 5403, 5541, 5709, 5985, 7371, 7539, 7869, 7917, 8397, 8445, 8547, 8793, 9051, 9057, 9915, 9933, 11067, 12153

Offset

1,1

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Example

n=3: n^4 = 81; {79,83} are primes.

Mathematica

lst={}; Do[p1=n^4-2; p2=n^4+2; If[PrimeQ[p1]&&PrimeQ[p2], AppendTo[lst, n]], {n, 0, 8!}]; lst (* Vladimir Joseph Stephan Orlovsky, Jan 17 2009 *)
Select[Range[730000], AllTrue[#^4 + {2, -2}, PrimeQ] &] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Jan 02 2018 *)

Crossrefs

Cf. A028870, A038599, A154831, A154832, A154833, A154834, A154933, A154934, A154935, A154936. - Vladimir Joseph Stephan Orlovsky, Jan 17 2009

Sequence in context: A112851 A253943 A034490 * A083231 A129755 A059826

Adjacent sequences: A071348 A071349 A071350 * A071352 A071353 A071354

Keyword

easy,nonn

Author

Labos Elemer, May 21 2002

Status

approved