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A020520 12th cyclotomic polynomial evaluated at powers of 2. 1
1, 13, 241, 4033, 65281, 1047553, 16773121, 268419073, 4294901761, 68719214593, 1099510579201, 17592181850113, 281474959933441, 4503599560261633, 72057593769492481, 1152921503533105153, 18446744069414584321, 295147905162172956673, 4722366482800925736961 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Colin Barker, Table of n, a(n) for n = 0..830

Index entries for linear recurrences with constant coefficients, signature (21,-84,64).

FORMULA

From Colin Barker, Feb 14 2015: (Start)

a(n) = 1-4^n+16^n.

a(n) = 21*a(n-1)-84*a(n-2)+64*a(n-3).

G.f.: -(52*x^2-8*x+1) / ((x-1)*(4*x-1)*(16*x-1)).

(End)

MAPLE

with(numtheory, cyclotomic):seq(cyclotomic(12, 2^i), i=0..24);

PROG

(PARI) a(n) = polcyclo(12, 2^n) \\ Colin Barker, Feb 14 2015

CROSSREFS

Sequence in context: A271782 A157969 A218229 * A259420 A203156 A049665

Adjacent sequences:  A020517 A020518 A020519 * A020521 A020522 A020523

KEYWORD

nonn,easy

AUTHOR

Simon Plouffe

STATUS

approved

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Last modified August 26 05:23 EDT 2019. Contains 326328 sequences. (Running on oeis4.)