A174366 Primes p such that 2*p^4-+15 are also prime.

2, 7, 163, 691, 719, 1129, 1493, 1609, 1693, 3709, 4397, 4423, 8171, 8231, 14387, 15259, 15749, 16553, 33053, 35999, 40151, 46573, 48487, 51721, 62383, 63863, 65717, 66271, 67411, 70051, 70111, 74419, 76333, 77047, 85549, 87421, 89923

Offset

1,1

Links

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

Example

For p=2, 2*2^4-+15=(17,47); p=2, 2*7^4-+15=(4787,4817).

Mathematica

okQ[n_]:=Module[{c=2n^4}, PrimeQ[c+15]&&PrimeQ[c-15]]; Select[Prime[ Range[ 8800]], okQ]  (* Harvey P. Dale, Apr 23 2011 *)
Select[Prime[Range[1000]], And@@PrimeQ[2 #^4 + {15, -15}]&] (* Vincenzo Librandi, Apr 10 2013 *)

Prog

(Magma) [p: p in PrimesUpTo(100000)|IsPrime(2*p^4-15) and IsPrime(2*p^4+15)];

Crossrefs

Sequence in context: A064607 A182974 A005345 * A177798 A077746 A236810

Adjacent sequences: A174363 A174364 A174365 * A174367 A174368 A174369

Keyword

nonn,easy

Author

Vincenzo Librandi, Mar 17 2010

Status

approved