A078030 Expansion of (1-x)/(1+2*x^3).

1, -1, 0, -2, 2, 0, 4, -4, 0, -8, 8, 0, 16, -16, 0, -32, 32, 0, 64, -64, 0, -128, 128, 0, 256, -256, 0, -512, 512, 0, 1024, -1024, 0, -2048, 2048, 0, 4096, -4096, 0, -8192, 8192, 0, 16384, -16384, 0, -32768, 32768, 0, 65536, -65536, 0, -131072, 131072, 0, 262144, -262144, 0, -524288, 524288, 0

Offset

0,4

Links

G. C. Greubel, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (0,0,-2).

Maple

seq(coeff(series((1-x)/(1+2*x^3), x, n+1), x, n), n = 0..60); # G. C. Greubel, Aug 05 2019

Mathematica

CoefficientList[Series[(1-x)/(1+2*x^3), {x, 0, 60}], x] (* G. C. Greubel, Aug 05 2019 *)

Prog

(PARI) my(x='x+O('x^60)); Vec((1-x)/(1+2*x^3)) \\ G. C. Greubel, Aug 05 2019
(Magma) R<x>:=PowerSeriesRing(Integers(), 60); Coefficients(R!( (1-x)/(1+2*x^3) )); // G. C. Greubel, Aug 05 2019
(Sage) ((1-x)/(1+2*x^3)).series(x, 60).coefficients(x, sparse=False) # G. C. Greubel, Aug 05 2019
(GAP) a:=[1, -1, 0];; for n in [4..60] do a[n]:=-2*a[n-3]; od; a; # G. C. Greubel, Aug 05 2019

Crossrefs

Sequence in context: A262967 A168090 A078029 * A262056 A264628 A241320

Adjacent sequences: A078027 A078028 A078029 * A078031 A078032 A078033

Keyword

sign

Author

N. J. A. Sloane, Nov 17 2002

Status

approved