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A078031
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Expansion of (1-x)/(1 + x^2 - x^3).
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2
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1, -1, -1, 2, 0, -3, 2, 3, -5, -1, 8, -4, -9, 12, 5, -21, 7, 26, -28, -19, 54, -9, -73, 63, 64, -136, -1, 200, -135, -201, 335, 66, -536, 269, 602, -805, -333, 1407, -472, -1740, 1879, 1268, -3619, 611, 4887, -4230, -4276, 9117, 46, -13393, 9071, 13439, -22464, -4368, 35903, -18096
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OFFSET
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0,4
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COMMENTS
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LINKS
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FORMULA
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G.f.: (1-x)/(1 + x^2 - x^3).
a(n) = -a(n-2) + a(n-3); a(0)=1, a(1)=-1, a(2)=-1. - Harvey P. Dale, Apr 08 2012
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MAPLE
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MATHEMATICA
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CoefficientList[Series[(1-x)/(1+x^2-x^3), {x, 0, 60}], x] (* or *) LinearRecurrence[{0, -1, 1}, {1, -1, -1}, 60] (* Harvey P. Dale, Apr 08 2012 *)
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PROG
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(Magma) R<x>:=PowerSeriesRing(Integers(), 60); Coefficients(R!( (1-x)/(1+x^2-x^3) )); // G. C. Greubel, Aug 05 2019
(Sage) ((1-x)/(1+x^2-x^3)).series(x, 60).coefficients(x, sparse=False) # G. C. Greubel, Aug 05 2019
(GAP) a:=[1, -1, -1];; for n in [4..60] do a[n]:=-a[n-2]+a[n-3]; od; a; # G. C. Greubel, Aug 05 2019
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CROSSREFS
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KEYWORD
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sign,easy
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AUTHOR
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STATUS
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approved
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