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%I #15 Apr 03 2017 13:55:47
%S 1,0,0,-1,0,0,1,0,0,0,0,0,0,0,0,1,0,0,-1,0,0,1,0,0,0,0,0,0,0,0,0,0,0,
%T 0,0,0,0,0,0,0,0,0,0,0,0,-1,0,0,1,0,0,-1,0,0,0,0,0,0,0,0,-1,0,0,1,0,0,
%U -1,0,0,0,0,0,0,0,0,0,0,0,0,0,0
%N Inverse of 90th cyclotomic polynomial.
%C Periodic with period length 90. - _Ray Chandler_, Apr 03 2017
%H Vincenzo Librandi, <a href="/A014099/b014099.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Rec#order_24">Index entries for linear recurrences with constant coefficients</a>, signature (0, 0, -1, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, -1, 0, 0, -1).
%H <a href="/index/Pol#poly_cyclo_inv">Index to sequences related to inverse of cyclotomic polynomials</a>
%p with(numtheory,cyclotomic); c := n->series(1/cyclotomic(n,x),x,80);
%t CoefficientList[Series[1/Cyclotomic[90, x], {x, 0, 200}], x] (* _Vincenzo Librandi_, Apr 06 2014 *)
%Y Cf. similar sequences listed in A240328 and A240465.
%K sign,easy
%O 0,1
%A _Simon Plouffe_