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A059721
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Mean of first six positive powers of n, i.e., (n + n^2 + n^3 + n^4 + n^5 + n^6)/6.
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7
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0, 1, 21, 182, 910, 3255, 9331, 22876, 49932, 99645, 185185, 324786, 542906, 871507, 1351455, 2034040, 2982616, 4274361, 6002157, 8276590, 11228070, 15009071, 19796491, 25794132, 33235300, 42385525, 53545401, 67053546
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OFFSET
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0,3
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LINKS
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FORMULA
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a(n) = (n^7 - n)/(6n - 6) = A053700(n)*n/6.
G.f.: x*(1+14*x+56*x^2+42*x^3+7*x^4)/(1-x)^7. [Colin Barker, May 08 2012]
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EXAMPLE
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a(2) = (2 + 4 + 8 + 16 + 32 + 64)/6 = 126/6 = 21.
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MATHEMATICA
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Table[Total[n^Range[6]]/6, {n, 0, 30}] (* Harvey P. Dale, Jan 29 2011 *)
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PROG
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(PARI) { for (n=0, 1000, if (n==1, a=1, a=(n^7 - n)/(6*n - 6)); write("b059721.txt", n, " ", a); ) } \\ Harry J. Smith, Jun 28 2009
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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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