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A145980
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a(n) = 29 + 73*n + 37*n^2.
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2
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29, 139, 323, 581, 913, 1319, 1799, 2353, 2981, 3683, 4459, 5309, 6233, 7231, 8303, 9449, 10669, 11963, 13331, 14773, 16289, 17879, 19543, 21281, 23093, 24979, 26939, 28973, 31081, 33263, 35519, 37849, 40253, 42731, 45283, 47909, 50609, 53383, 56231, 59153, 62149, 65219, 68363
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OFFSET
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0,1
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LINKS
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FORMULA
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a(n) = 3*a(n-1)-3*a(n-2)+a(n-3).
G.f.: (29+52*x-7*x^2)/(1-x)^3. (End)
E.g.f.: (37*x^2 + 110*x + 29)*exp(x). - G. C. Greubel, Jan 29 2016
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MATHEMATICA
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LinearRecurrence[{3, -3, 1}, {29, 139, 323}, 50] (* G. C. Greubel, Jan 29 2016 *)
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PROG
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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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EXTENSIONS
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Indices in definition edited, extended beyond a(13) by R. J. Mathar, Oct 31 2008
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STATUS
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approved
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