OFFSET
0,6
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (1,1,-2).
FORMULA
a(0)=1, a(1)=0, a(2)=1, a(n) = a(n-1) + a(n-2) - 2*a(n-3). - Harvey P. Dale, May 04 2013
MATHEMATICA
CoefficientList[Series[(1-x)/(1-x-x^2+2x^3), {x, 0, 60}], x] (* or *) LinearRecurrence[ {1, 1, -2}, {1, 0, 1}, 60] (* Harvey P. Dale, May 04 2013 *)
PROG
(PARI) my(x='x+O('x^60)); Vec((1-x)/(1-x-x^2+2*x^3)) \\ G. C. Greubel, Jun 28 2019
(Magma) R<x>:=PowerSeriesRing(Integers(), 60); Coefficients(R!( (1-x)/(1-x-x^2+2*x^3) )); // G. C. Greubel, Jun 28 2019
(Sage) ((1-x)/(1-x-x^2+2*x^3)).series(x, 60).coefficients(x, sparse=False) # G. C. Greubel, Jun 28 2019
(GAP) a:=[1, 0, 1];; for n in [4..60] do a[n]:=a[n-1]+a[n-2]-2*a[n-3]; od; a; # G. C. Greubel, Jun 28 2019
CROSSREFS
KEYWORD
sign,easy
AUTHOR
N. J. A. Sloane, Nov 17 2002
STATUS
approved