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A077955
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Expansion of 1/(1-x+2*x^2+x^3).
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2
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1, 1, -1, -4, -3, 6, 16, 7, -31, -61, -6, 147, 220, -68, -655, -739, 639, 2772, 2233, -3950, -11188, -5521, 20805, 43035, 6946, -99929, -156856, 36056, 449697, 534441, -401009, -1919588, -1652011, 2588174, 7811784, 4287447, -13924295, -30310973, -6749830, 67796411, 111607044, -17235948
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OFFSET
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0,4
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LINKS
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FORMULA
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MATHEMATICA
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LinearRecurrence[{1, -2, -1}, {1, 1, -1}, 50] (* or *) CoefficientList[ Series[1/(1-x+2*x^2+x^3), {x, 0, 50}], x] (* G. C. Greubel, Jul 02 2019 *)
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PROG
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(Magma) R<x>:=PowerSeriesRing(Integers(), 50); Coefficients(R!( 1/(1-x+2*x^2+x^3) )); // G. C. Greubel, Jul 02 2019
(Sage) (1/(1-x+2*x^2+x^3)).series(x, 50).coefficients(x, sparse=False) # G. C. Greubel, Jul 02 2019
(GAP) a:=[1, 1, -1];; for n in [4..50] do a[n]:=a[n-1]-2*a[n-2]-a[n-3]; od; a; # G. C. Greubel, Jul 02 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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