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%I #11 Mar 22 2015 17:58:43
%S 3,73,757,19,829,2467,37,1063,262657,333667,1772893,80749,1609669,397,
%T 18973,541,21061,109,1270657,991,34327,523,29989,64008001,85775383,
%U 127,297613,7792003,2017,4987,5167,308933353,433,8209,444979,14437,41203,729027001
%N Primitive prime factors of the cyclotomic polynomial sequence Phi(9,k) in the order in which they occur.
%C Phi(9,k) = k^6 + k^3 + 1.
%H Robert Price, <a href="/A256144/b256144.txt">Table of n, a(n) for n = 1..1521</a>
%t prim = {}; Do[prim = Join[prim, Complement[First /@ FactorInteger[Cyclotomic[9, k]], prim]], {k, 1000}]; prim
%o (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
%Y Cf. A005529, A248874.
%K nonn
%O 1,1
%A _Robert Price_, Mar 16 2015