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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
LINKS
Mohammed L. Nadji, Moussa Ahmia, Daniel F. Checa, and José L. Ramírez, Arndt Compositions with Restricted Parts, Palindromes, and Colored Variants, J. Int. Seq. (2025) Vol. 28, Issue 3, Article 25.3.6. See p. 8.
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