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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
OFFSET
0,2
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);
MATHEMATICA
Cyclotomic[12, 2^Range[0, 20]] (* Paolo Xausa, Sep 16 2024 *)
PROG
(PARI) a(n) = polcyclo(12, 2^n) \\ Colin Barker, Feb 14 2015
CROSSREFS
Sequence in context: A271782 A157969 A218229 * A259420 A203156 A049665
KEYWORD
nonn,easy
AUTHOR
STATUS
approved