A250182 Numbers n such that Phi_28(n) is prime, where Phi is the cyclotomic polynomial.

4, 5, 7, 13, 25, 33, 41, 63, 74, 80, 88, 94, 96, 104, 116, 144, 149, 151, 154, 165, 167, 174, 183, 191, 197, 208, 231, 241, 262, 268, 270, 290, 318, 319, 361, 368, 376, 390, 394, 412, 431, 434, 442, 464, 489, 492, 521, 529, 556, 568, 574, 575, 585, 589, 613, 629, 639, 654, 666, 667, 672, 683, 684

Offset

1,1

Links

G. C. Greubel, Table of n, a(n) for n = 1..10000

Mathematica

Select[Range[700], PrimeQ[Cyclotomic[28, #]] &] (* Vincenzo Librandi, Jan 17 2015 *)

Prog

(PARI) isok(n) = isprime(polcyclo(28, n)); \\ Michel Marcus, Jan 17 2015

Crossrefs

Cf. A246392.

Sequence in context: A293757 A275273 A069575 * A358701 A072215 A106170

Adjacent sequences: A250179 A250180 A250181 * A250183 A250184 A250185

Keyword

nonn

Author

R. J. Mathar, Jan 09 2015

Status

approved