A250190 Numbers n such that Phi(42,n) is prime, where Phi is the cyclotomic polynomial.

2, 6, 8, 11, 23, 35, 41, 49, 58, 65, 85, 88, 97, 107, 111, 139, 144, 161, 170, 197, 214, 217, 223, 230, 238, 247, 274, 298, 301, 323, 382, 389, 393, 398, 403, 427, 445, 452, 473, 480, 497, 511, 561, 575, 595, 601, 604, 606, 615, 629, 651, 652, 680, 685, 702, 725, 762, 770, 774, 781, 805, 814, 912, 918, 942, 987, 1030

Offset

1,1

Links

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

Mathematica

Select[Range[1100], PrimeQ[Cyclotomic[42, #]] &] (* Vincenzo Librandi, Jan 16 2015 *)

Prog

(PARI) {is(n)=isprime(polcyclo(42, n))};
for(n=1, 1000, if(is(n)==1, print1(n, ", "))) \\ G. C. Greubel, May 18 2018

Crossrefs

Cf. A246392.

Sequence in context: A076991 A130205 A054067 * A244342 A064212 A056906

Adjacent sequences: A250187 A250188 A250189 * A250191 A250192 A250193

Keyword

nonn

Author

R. J. Mathar, Jan 12 2015

Status

approved