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A078028 Expansion of (1-x)/(1-x^2+2*x^3). 5
1, -1, 1, -3, 3, -5, 9, -11, 19, -29, 41, -67, 99, -149, 233, -347, 531, -813, 1225, -1875, 2851, -4325, 6601, -10027, 15251, -23229, 35305, -53731, 81763, -124341, 189225, -287867, 437907, -666317, 1013641, -1542131, 2346275, -3569413, 5430537, -8261963, 12569363, -19123037, 29093289 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

COMMENTS

Number of compositions of n into parts congruent to (0,2} mod 3 (offset 2). - Vladeta Jovovic, Feb 09 2005

LINKS

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

Index entries for linear recurrences with constant coefficients, signature (0,1,-2).

MAPLE

seq(coeff(series((1-x)/(1-x^2+2*x^3), x, n+1), x, n), n = 0..60); # G. C. Greubel, Aug 04 2019

MATHEMATICA

CoefficientList[Series[(1-x)/(1-x^2+2*x^3), {x, 0, 60}], x] (* G. C. Greubel, Aug 04 2019 *)

PROG

(PARI) Vec((1-x)/(1-x^2+2*x^3)+O(x^60)) \\ Charles R Greathouse IV, Sep 25 2012

(MAGMA) R<x>:=PowerSeriesRing(Integers(), 60); Coefficients(R!( (1-x)/(1-x^2+2*x^3) )); // G. C. Greubel, Aug 04 2019

(Sage) ((1-x)/(1-x^2+2*x^3)).series(x, 60).coefficients(x, sparse=False) # G. C. Greubel, Aug 04 2019

(GAP) a:=[1, -1, 1];; for n in [4..60] do a[n]:=a[n-2]-2*a[n-3]; od; a; # G. C. Greubel, Aug 04 2019

CROSSREFS

Sequence in context: A072706 A117433 A159284 * A317142 A279375 A245143

Adjacent sequences:  A078025 A078026 A078027 * A078029 A078030 A078031

KEYWORD

sign,easy

AUTHOR

N. J. A. Sloane, Nov 17 2002

STATUS

approved

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Last modified September 27 19:23 EDT 2021. Contains 347694 sequences. (Running on oeis4.)