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A120287
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Numerator of 1/n^3 + 2/(n-1)^3 + 3/(n-2)^3 +...+ (n-1)/2^3 + n.
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0
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1, 17, 355, 7715, 203413, 492527, 49601051, 1823359051, 16684019407, 186004308017, 22757931053507, 298630937704541, 50872538998767329, 51223731720255509, 103063783892301061, 7045407930432340853
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| p divides a(p-1) and a(p-2) for prime p>3.
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FORMULA
| a(n) = numerator[Sum[Sum[1/i^3,{i,1,k}],{k,1,n}]].
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MATHEMATICA
| Numerator[Table[Sum[Sum[1/i^3, {i, 1, k}], {k, 1, n}], {n, 1, 25}]]
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CROSSREFS
| Cf. A001008, A007406, A007407, A007408, A007410.
Sequence in context: A194729 A081421 A121824 * A002197 A070148 A097499
Adjacent sequences: A120284 A120285 A120286 * A120288 A120289 A120290
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KEYWORD
| frac,nonn
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AUTHOR
| Alexander Adamchuk (alex(AT)kolmogorov.com), Jul 07 2006
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