A020520 12th cyclotomic polynomial evaluated at powers of 2.

1, 13, 241, 4033, 65281, 1047553, 16773121, 268419073, 4294901761, 68719214593, 1099510579201, 17592181850113, 281474959933441, 4503599560261633, 72057593769492481, 1152921503533105153, 18446744069414584321, 295147905162172956673, 4722366482800925736961

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