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A014017
Inverse of 8th cyclotomic polynomial.
9
1, 0, 0, 0, -1, 0, 0, 0, 1, 0, 0, 0, -1, 0, 0, 0, 1, 0, 0, 0, -1, 0, 0, 0, 1, 0, 0, 0, -1, 0, 0, 0, 1, 0, 0, 0, -1, 0, 0, 0, 1, 0, 0, 0, -1, 0, 0, 0, 1, 0, 0, 0, -1, 0, 0, 0, 1, 0, 0, 0, -1, 0, 0, 0, 1, 0, 0, 0, -1, 0, 0, 0, 1, 0, 0, 0, -1, 0, 0, 0, 1
OFFSET
0,1
COMMENTS
Periodic with period length 8. - Ray Chandler, Apr 03 2017
FORMULA
a(4n) = (-1)^n, else a(n) = 0.
G.f.: 1/ ( 1+x^4 ). - R. J. Mathar, Mar 11 2011
a(n) = sin((sin(Pi*(n+1)/2)^2)*Pi*(n+2)/4). - Mikael Aaltonen, Jan 02 2015
E.g.f.: cos(x/sqrt(2))*cosh(x/sqrt(2)). - Vaclav Kotesovec, Feb 15 2015
MAPLE
with(numtheory, cyclotomic); c := n->series(1/cyclotomic(n, x), x, 80);
MATHEMATICA
CoefficientList[Series[1/Cyclotomic[8, x], {x, 0, 100}], x] (* Vincenzo Librandi, Apr 03 2014 *)
PROG
(PARI) Vec(1/polcyclo(8)+O(x^99)) \\ Charles R Greathouse IV, Mar 24 2014
(Magma) &cat[[1, 0, 0, 0, -1, 0, 0, 0]: n in [0..20]]; // Vincenzo Librandi, Apr 03 2014
CROSSREFS
Sequence in context: A015153 A015985 A015777 * A121262 A181923 A339825
KEYWORD
sign,easy
AUTHOR
STATUS
approved