A231613 Numbers n such that the four sixth-degree cyclotomic polynomials are simultaneously prime.

32034, 162006, 339105, 458811, 1780425, 2989119, 2993100, 3080205, 4375404, 6129597, 6280221, 7565142, 8489820, 10268277, 11343741, 12065076, 13067295, 13333182, 15866508, 16472802, 17040537, 18028605, 19066758, 22633629, 24256362, 24365259, 25031349

Offset: 1

Author

T. D. Noe, Dec 11 2013

Keywords

• nonn

Comments

The polynomials are cyclotomic(7,x) = 1 + x + x^2 + x^3 + x^4 + x^5 + x^6, cyclotomic(9,x) = 1 + x^3 + x^6, cyclotomic(14,x) = 1 - x + x^2 - x^3 + x^4 - x^5 + x^6, and cyclotomic(18,x) = 1 - x^3 + x^6. The numbers 7, 9, 14 and 18 are in the sixth row of A032447.

By Schinzel's hypothesis H, there are an infinite number of n that yield simultaneous primes. Note that the two first-degree cyclotomic polynomials, x-1 and x+1, yield the twin primes for the numbers in A014574.

References

• See A087277.

Crossrefs

Cf. A014574 (first degree solutions: average of twin primes).

Cf. A087277 (similar, but with second-degree cyclotomic polynomials).

Cf. A231612 (similar, but with fourth-degree cyclotomic polynomials).

Cf. A231614 (similar, but with eighth-degree cyclotomic polynomials).

Programs

Mathematica

t = {}; n = 0; While[Length[t] < 30, n++; If[PrimeQ[Cyclotomic[7, n]] && PrimeQ[Cyclotomic[9, n]] && PrimeQ[Cyclotomic[14, n]] && PrimeQ[Cyclotomic[18, n]], AppendTo[t, n]]]; t
Select[Range[251*10^5],AllTrue[Cyclotomic[{7,9,14,18},#],PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Oct 29 2016 *)