OFFSET
0,1
COMMENTS
Periodic with period length 22. - Ray Chandler, Apr 03 2017
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (1, -1, 1, -1, 1, -1, 1, -1, 1, -1).
FORMULA
G.f.: 1/(1 - x + x^2 - x^3 + ... - x^9 + x^10). - R. J. Mathar, Aug 11 2012
From Luce ETIENNE, Nov 04 2018: (Start)
a(n) = a(n-22).
a(n) = (-9*m^10 + 485*m^9 - 11340*m^8 + 150690*m^7 - 1251117*m^6 + 6709605*m^5 - 23140710*m^4 + 49127860*m^3 - 57244824*m^2 + 25659360*m + 3628800)*(-1)^floor(n/11)/3628800 where m = (n mod 11). (End)
MAPLE
with(numtheory, cyclotomic); c := n->series(1/cyclotomic(n, x), x, 80);
MATHEMATICA
CoefficientList[Series[1/Cyclotomic[22, x], {x, 0, 100}], x] (* Vincenzo Librandi, Apr 03 2014 *)
LinearRecurrence[{1, -1, 1, -1, 1, -1, 1, -1, 1, -1}, {1, 1, 0, 0, 0, 0, 0, 0, 0, 0}, 81] (* Ray Chandler, Sep 15 2015 *)
PROG
(PARI) Vec(1/polcyclo(22)+O(x^99)) \\ Charles R Greathouse IV, Mar 24 2014
(Magma) &cat[[1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0]: n in [0..6]]; // Vincenzo Librandi, Apr 03 2014
CROSSREFS
KEYWORD
sign,easy
AUTHOR
STATUS
approved