A256144 Primitive prime factors of the cyclotomic polynomial sequence Phi(9,k) in the order in which they occur.

3, 73, 757, 19, 829, 2467, 37, 1063, 262657, 333667, 1772893, 80749, 1609669, 397, 18973, 541, 21061, 109, 1270657, 991, 34327, 523, 29989, 64008001, 85775383, 127, 297613, 7792003, 2017, 4987, 5167, 308933353, 433, 8209, 444979, 14437, 41203, 729027001

Offset

1,1

Comments

Phi(9,k) = k^6 + k^3 + 1.

Links

Robert Price, Table of n, a(n) for n = 1..1521

Mathematica

prim = {}; Do[prim = Join[prim, Complement[First /@ FactorInteger[Cyclotomic[9, k]], prim]], {k, 1000}]; prim

Prog

(PARI) lista(nn) = {vs = []; for (n=1, nn, vp = factor(polcyclo(9, n))[, 1]; for (i=1, #vp, if (!vecsearch(vs, vp[i]), print1(vp[i], ", "); vs = vecsort(concat(vs, vp[i]), , 8); ); ); ); } \\ Michel Marcus, Mar 20 2015

Crossrefs

Cf. A005529, A248874.

Sequence in context: A142078 A054689 A371511 * A060883 A162601 A173807

Adjacent sequences: A256141 A256142 A256143 * A256145 A256146 A256147

Keyword

nonn

Author

Robert Price, Mar 16 2015

Status

approved