A165353 Primes p such that p+(p^2-1)/8 is a prime number.

7, 17, 23, 31, 41, 71, 73, 79, 103, 113, 127, 151, 191, 233, 257, 281, 311, 337, 367, 383, 409, 433, 463, 487, 569, 577, 593, 601, 607, 647, 809, 887, 911, 953, 977, 1039, 1049, 1087, 1097, 1153, 1193, 1201, 1223, 1279, 1297, 1321, 1361, 1399, 1433, 1481, 1487

Offset

1,1

Links

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

Formula

a(n)+(a(n)^2-1)/8 = A165352(n).

Mathematica

Select[Prime[Range[250]], PrimeQ[# + (#^2 - 1)/8] &] (* Vincenzo Librandi, Sep 01 2012 *)

Prog

(Magma) [n: n in [3..1500] |IsPrime(n) and IsPrime(n+(n^2-1) div 8)]; // Vincenzo Librandi, Sep 01 2012

Crossrefs

Cf. A165352, A165354.

Sequence in context: A001132 A308816 A254678 * A048976 A088546 A265816

Adjacent sequences: A165350 A165351 A165352 * A165354 A165355 A165356

Keyword

nonn,easy

Author

Vincenzo Librandi, Sep 16 2009

Extensions

More terms from R. J. Mathar, Sep 21 2009

Status

approved