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A049000
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Sum of sigma(j) for 1<=j<10^n, where sigma(j) is the sum of divisors of j.
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4
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0, 69, 8082, 820741, 82231803, 8224494757, 822465638000, 82246686892516, 8224670172682646, 822467031614802290, 82246703327412473943, 8224670334073621455209, 822467033422857645316807, 82246703342395510922780776, 8224670334240978188556405240
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OFFSET
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0,2
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COMMENTS
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The ratio of successive terms approaches 100.
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LINKS
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FORMULA
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EXAMPLE
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For n=1, the sum of sigma(j) for j<10 is 1+3+4+7+6+12+8+15+13=69, so a(1)=69.
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CROSSREFS
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Cf. A072692 (sum for 1<=j<=10^n and other links).
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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