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A225393
Expansion of 1/(1 - x - x^2 + x^6 - x^8).
24
1, 1, 2, 3, 5, 8, 12, 19, 30, 47, 74, 116, 183, 288, 453, 713, 1122, 1766, 2779, 4373, 6882, 10830, 17043, 26820, 42206, 66419, 104522, 164484, 258845, 407339, 641021, 1008761, 1587466, 2498162, 3931305, 6186612, 9735741, 15320931, 24110227, 37941757, 59708145
OFFSET
0,3
FORMULA
G.f.: 1/(1 - x - x^2 + x^6 - x^8).
a(n) = a(n-1) + a(n-2) - a(n-6) + a(n-8). - Ilya Gutkovskiy, Nov 16 2016
MATHEMATICA
CoefficientList[Series[1/(1 - x - x^2 + x^6 - x^8), {x, 0, 50}], x]
LinearRecurrence[{1, 1, 0, 0, 0, -1, 0, 1}, {1, 1, 2, 3, 5, 8, 12, 19}, 50] (* G. C. Greubel, Nov 16 2016 *)
PROG
(PARI) Vec(1/(1-x-x^2+x^6-x^8) + O(x^50)) \\ G. C. Greubel, Nov 16 2016
(Magma) m:=50; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/(1-x-x^2+x^6-x^8))); // G. C. Greubel, Nov 03 2018
KEYWORD
nonn,easy
AUTHOR
Roger L. Bagula, May 06 2013
STATUS
approved