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A256146 Primitive prime factors of the cyclotomic polynomial sequence Phi(7,k) in the order in which they occur. 3
7, 127, 1093, 43, 19531, 55987, 29, 4733, 337, 547, 239, 4649, 45319, 659, 4943, 5229043, 8108731, 1743463, 113, 25646167, 449, 80207, 701, 70841, 71, 32719, 631, 3319, 16968421, 5336717, 28771, 321272407, 368089, 4422461, 88009573, 93997, 917087137, 122921 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Phi(7,k) = k^6 + k^5 + k^4 + k^3 + k^2 + k + 1.

LINKS

Robert Price, Table of n, a(n) for n = 1..1511

MATHEMATICA

prim = {}; Do[prim = Join[prim, Complement[First /@ FactorInteger[Cyclotomic[7, k]], prim]], {k, 1000}]; prim

PROG

(PARI) lista(nn) = {vs = []; for (n=1, nn, vp = factor(polcyclo(7, 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, A256144, A256145.

Sequence in context: A246648 A139987 A061744 * A053716 A088550 A255954

Adjacent sequences:  A256143 A256144 A256145 * A256147 A256148 A256149

KEYWORD

nonn

AUTHOR

Robert Price, Mar 16 2015

STATUS

approved

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Last modified March 26 12:43 EDT 2019. Contains 321497 sequences. (Running on oeis4.)