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A084643
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a(n) = 3^(n-1)*(2*n-3) + 2^(n+1).
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3
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1, 3, 11, 43, 167, 631, 2315, 8275, 28943, 99439, 336659, 1126027, 3728279, 12239527, 39890843, 129205699, 416249375, 1334710495, 4262149667, 13560765691, 43005771431, 135988785943, 428882869931, 1349402340403
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OFFSET
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0,2
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COMMENTS
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Binomial transform of A048495. Second binomial transform of 1, 1, 3, 5, 7, ...
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LINKS
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FORMULA
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G.f.: (1 - 5*x + 8*x^2)/((1-2*x)*(1-3*x)^2). - Colin Barker, Mar 22 2012
E.g.f.: 2*exp(2*x) + (2*x-1)*exp(3*x). - G. C. Greubel, Mar 22 2023
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MATHEMATICA
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LinearRecurrence[{8, -21, 18}, {1, 3, 11}, 30] (* Harvey P. Dale, Dec 12 2015 *)
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PROG
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(SageMath) [2^(n+1) +3^(n-1)*(2*n-3) for n in range(41)] # G. C. Greubel, Mar 22 2023
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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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