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A225394 Expansion of 1/(1 - x - x^2 + x^7 - x^9). 24
1, 1, 2, 3, 5, 8, 13, 20, 32, 51, 81, 129, 205, 326, 519, 826, 1314, 2091, 3327, 5294, 8424, 13404, 21328, 33937, 54000, 85924, 136721, 217548, 346159, 550803, 876429, 1394560, 2219002, 3530841, 5618219, 8939622, 14224586, 22633938, 36014767, 57306132, 91184618 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
COMMENTS
Limiting ratio is 1.59118..., the largest real root of -1 + x^2 - x^7 - x^8 + x^9 = 0.
LINKS
FORMULA
a(n) = a(n-1) + a(n-2) - a(n-7) + a(n-9). - Ilya Gutkovskiy, Nov 16 2016
MATHEMATICA
CoefficientList[Series[1/(1 - x - x^2 + x^7 - x^9), {x, 0, 50}], x]
LinearRecurrence[{1, 1, 0, 0, 0, 0, -1, 0, 1}, {1, 1, 2, 3, 5, 8, 13, 20, 32}, 50] (* G. C. Greubel, Nov 16 2016 *)
PROG
(PARI) Vec(1/(1-x-x^2+x^7-x^9) + 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^7-x^9))); // G. C. Greubel, Nov 03 2018
CROSSREFS
Sequence in context: A055805 A023437 A322332 * A013985 A092834 A080106
KEYWORD
nonn,easy
AUTHOR
Roger L. Bagula, May 06 2013
STATUS
approved

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Last modified July 21 14:09 EDT 2024. Contains 374474 sequences. (Running on oeis4.)