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A153267
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a(n) = -4*a(n-3) + 11*a(n-2) - a(n-1), a(0) = -5, a(1) = 39, a(2) = -110.
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4
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-5, 39, -110, 559, -1925, 8514, -31925, 133279, -518510, 2112279, -8349005, 33658114, -133946285, 537581559, -2145623150, 8594805439, -34346986325, 137472338754, -549668410085, 2199252081679, -8795493947630, 35185940486439
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OFFSET
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0,1
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COMMENTS
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A153266(n) + a(n) = 4*A001519(n) (apart from initial terms). The generating floretion Z = X*Y with X = 1.5'i + 0.5i' + .25(ii + jj + kk + ee) and Y = 0.5'i + 1.5i' + .25(ii + jj + kk + ee).
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LINKS
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FORMULA
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a(n) = 2*(-4)^n + 3/2+1/2*sqrt(5))^n + (3/2-1/2*sqrt(5))^n.
G.f.: -(16*x^2-34*x+5) / ((4*x+1)*(x^2-3*x+1)). - Colin Barker, Jun 25 2014
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EXAMPLE
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a(4) = -1*559 + 11*(-110) - 4*(39) = -1925.
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MATHEMATICA
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CoefficientList[Series[-(16 x^2 - 34 x + 5)/((4 x + 1) (x^2 - 3 x + 1)), {x, 0, 30}], x] (* Vincenzo Librandi, Jun 26 2014 *)
LinearRecurrence[{-1, 11, -4}, {-5, 39, -110}, 30] (* Harvey P. Dale, Mar 02 2023 *)
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PROG
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(PARI) Vec(-(16*x^2-34*x+5)/((4*x+1)*(x^2-3*x+1)) + O(x^100)) \\ Colin Barker, Jun 25 2014
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CROSSREFS
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KEYWORD
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easy,sign
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AUTHOR
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STATUS
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approved
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