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A220083
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a(n) = (15*n^2 + 9*n + 2)/2.
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8
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1, 13, 40, 82, 139, 211, 298, 400, 517, 649, 796, 958, 1135, 1327, 1534, 1756, 1993, 2245, 2512, 2794, 3091, 3403, 3730, 4072, 4429, 4801, 5188, 5590, 6007, 6439, 6886, 7348, 7825, 8317, 8824, 9346, 9883, 10435, 11002, 11584, 12181, 12793, 13420, 14062
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OFFSET
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0,2
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COMMENTS
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Other similar sequences:
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LINKS
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FORMULA
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G.f.: (1+10*x+4*x^2)/(1-x)^3.
Sum( a(i), i=0..n ) = A006597(n+1).
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MAPLE
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MATHEMATICA
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Table[(15 n^2 + 9 n + 2)/2, {n, 0, 45}]
CoefficientList[Series[(1 + 10 x + 4 x^2) / (1 - x)^3, {x, 0, 50}], x] (* Vincenzo Librandi, Aug 18 2013 *)
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PROG
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(Magma) /* By first comment: */ A000566:=func<n | n*(5*n-3)/2>; [n*A000566(n)-(n-1)*A000566(n-1): n in [1..45]];
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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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