OFFSET
0,3
COMMENTS
Limiting ratio is 1.5452156..., the real root of x^7 - x^6 - x^5 + x^2 - 1.
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (1,1,0,0,-1,0,1).
FORMULA
a(n) = a(n-1) + a(n-2) - a(n-5) + a(n-7). - Franck Maminirina Ramaharo, Nov 02 2018
MAPLE
seq(coeff(series(1/(1-x-x^2+x^5-x^7), x, n+1), x, n), n = 0..50); # G. C. Greubel, Mar 16 2020
MATHEMATICA
CoefficientList[Series[1/(1 - x - x^2 + x^5 - x^7), {x, 0, 50}], x]
LinearRecurrence[{1, 1, 0, 0, -1, 0, 1}, {1, 1, 2, 3, 5, 7, 11}, 50] (* Harvey P. Dale, Aug 28 2013 *)
PROG
(PARI) my(x='x+O('x^50)); Vec(1/(1-x-x^2+x^5-x^7)) \\ G. C. Greubel, Nov 16 2016
(Magma) m:=50; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/(1-x-x^2+x^5-x^7))); // G. C. Greubel, Nov 03 2018
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Roger L. Bagula, Jan 17 2012
STATUS
approved