A227516 Values of n such that L(13) and N(13) are both prime, where L(k) = (n^2+n+1)*2^(2*k) + (2*n+1)*2^k + 1, N(k) = (n^2+n+1)*2^k + n.

25, -33, -285, 325, 349, -449, -621, 661, 843, 975, -977, 991, 1035, -1037, -1137, -1191, -1515, -1593, -1625, 1683, 1693, -1713, 1759, -1803, 1957, 2125, 2523, -2531, -2615, 2827, -2901, -2999, 3033, -3147, 3373, 3391, 3559, 3621, 3663, -3795, 3849, -3855, 3891, 3957, -3993, -4085, -4317, -4323, -4407, 4531, -4617, 4633

Offset

1,1

Comments

Computed with PARI using commands similar to those used to compute A226921.

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..278

Eric L. F. Roettger, A cubic extension of the Lucas functions, Thesis, Dept. of Mathematics and Statistics, Univ. of Calgary, 2009. See page 195.

Crossrefs

Cf. A226921-A226929, A227448, A227449, A227515-A227523.

Sequence in context: A075452 A231572 A020258 * A281369 A188059 A257720

Adjacent sequences: A227513 A227514 A227515 * A227517 A227518 A227519

Keyword

sign,easy

Author

Vincenzo Librandi, Jul 14 2013

Status

approved