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A081894
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Fourth binomial transform of C(n+2,2).
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3
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1, 7, 46, 290, 1775, 10625, 62500, 362500, 2078125, 11796875, 66406250, 371093750, 2060546875, 11376953125, 62500000000, 341796875000, 1861572265625, 10101318359375, 54626464843750, 294494628906250, 1583099365234375
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OFFSET
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0,2
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COMMENTS
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4th binomial transform of C(n+2,2), A000217.
5th binomial transform of (1,2,1,0,0,0,.....)
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LINKS
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FORMULA
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a(n) = 5^n*(n^2 + 19*n + 50)/50.
G.f.: (1 - 4*x)^2/(1 - 5*x)^3.
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MATHEMATICA
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LinearRecurrence[{15, -75, 125}, {1, 7, 46}, 50] (* G. C. Greubel, Oct 18 2018 *)
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PROG
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(PARI) x='x+O('x^30); Vec((1-4*x)^2/(1-5*x)^3) \\ G. C. Greubel, Oct 18 2018
(Magma) m:=30; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!((1-4*x)^2/(1-5*x)^3)); // G. C. Greubel, Oct 18 2018
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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