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A321675
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a(n) = Sum_{k=1..10^n} k*sigma(k).
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0
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1, 622, 558275, 549175530, 548429473046, 548320905633448, 548312690631798482, 548311465139943768941, 548311366911386862908968, 548311356554322895313137239, 548311355740964925044531454428, 548311355626818302486560961291870, 548311355617569600726982364186141942
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OFFSET
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0,2
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LINKS
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FORMULA
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a(n) ~ 10^(3*n) * Pi^2 / 18.
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MATHEMATICA
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PROG
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(PARI) a(n) = sum(k=1, 10^n, k*sigma(k)); \\ Michel Marcus, Nov 23 2018
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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