A165567 Primes of the form (p^2 - 1)/8 - p, where p is also a prime.

19, 43, 89, 229, 593, 701, 1223, 1483, 1889, 2699, 3319, 4463, 4751, 6553, 7019, 11779, 11933, 13859, 19699, 23003, 28201, 31123, 33409, 39901, 41039, 44549, 49139, 51679, 63901, 81001, 83843, 87151, 92233, 97459, 102829, 104651, 112573, 131839, 136501

Offset

1,1

Comments

The associated p are in A165566.

Links

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

Example

p=17 generates a(1) = 19 = (17^2-1)/8 -17. p=23 generates a(2) = 43 = (23^2-1)/8-23.

Mathematica

Select[Table[(p^2 - 1)/8 - p, {p, Prime[Range[4, 200]]}], PrimeQ] (* Vincenzo Librandi, Oct 12 2012 *)

Prog

(Magma) [a: p in PrimesInInterval(6, 1200) | IsPrime(a) where a is (p^2 - 1) div 8 - p ]; // Vincenzo Librandi, Oct 12 2012

Crossrefs

Cf. A165566.

Sequence in context: A078561 A074222 A054820 * A205533 A185167 A140619

Adjacent sequences: A165564 A165565 A165566 * A165568 A165569 A165570

Keyword

nonn,easy

Author

Vincenzo Librandi, Sep 22 2009

Extensions

Sequence extended by R. J. Mathar, Oct 16 2009

Status

approved