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A256857
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a(n) = n*(n^2 + 3*n - 2)/2.
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2
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0, 1, 8, 24, 52, 95, 156, 238, 344, 477, 640, 836, 1068, 1339, 1652, 2010, 2416, 2873, 3384, 3952, 4580, 5271, 6028, 6854, 7752, 8725, 9776, 10908, 12124, 13427, 14820, 16306, 17888, 19569, 21352, 23240, 25236, 27343, 29564, 31902, 34360, 36941, 39648, 42484, 45452, 48555
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OFFSET
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0,3
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COMMENTS
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The sequence is the 5th upper diagonal of the array in A139600.
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LINKS
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FORMULA
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G.f.: x*(1 + 4*x -2*x^2)/(1 - x)^4.
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MATHEMATICA
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Table[n (n^2 + 3 n - 2)/2, {n, 0, 40}]
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PROG
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(PARI) vector(50, n, n--; n*(n^2+3*n-2)/2) \\ Bruno Berselli, Apr 15 2015
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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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STATUS
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approved
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