OFFSET
0,5
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
G.f.: (1-x)/(1-x+x^2-2*x^3).
MATHEMATICA
LinearRecurrence[{1, -1, 2}, {1, 0, -1}, 60] (* or *) CoefficientList[Series[ (1-x)/(1-x+x^2-2*x^3), {x, 0, 60}], x] (* G. C. Greubel, Jun 29 2019 *)
PROG
(PARI) my(x='x+O('x^60)); Vec((1-x)/(1-x+x^2-2*x^3)) \\ G. C. Greubel, Jun 29 2019
(Magma) R<x>:=PowerSeriesRing(Integers(), 60); Coefficients(R!( (1-x)/(1-x+x^2-2*x^3) )); // G. C. Greubel, Jun 29 2019
(Sage) ((1-x)/(1-x+x^2-2*x^3)).series(x, 60).coefficients(x, sparse=False) # G. C. Greubel, Jun 29 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 29 2019
CROSSREFS
KEYWORD
sign
AUTHOR
N. J. A. Sloane, Nov 17 2002
STATUS
approved