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A225391
Expansion of 1/(1 - x - x^2 - x^6 + x^8).
27
1, 1, 2, 3, 5, 8, 14, 23, 38, 63, 104, 172, 285, 472, 781, 1293, 2140, 3542, 5863, 9705, 16064, 26590, 44013, 72852, 120588, 199603, 330392, 546880, 905221, 1498363, 2480159, 4105273, 6795236, 11247786, 18617851, 30817120, 51009909, 84433939, 139758925
OFFSET
0,3
COMMENTS
Limiting ratio is 1.65525..., the largest real root of 1 - x^2 - x^6 - x^7 + x^8.
FORMULA
a(n) = a(n-1) + a(n-2) + a(n-6) - a(n-8). - Franck Maminirina Ramaharo, Nov 02 2018
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, 14, 23}, 100] (* 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