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A366613
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Sum of the divisors of 5^n-1.
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11
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7, 60, 224, 1736, 6048, 49920, 136724, 1107792, 3718400, 27060480, 85449224, 869499904, 2136230474, 15820920000, 61359427584, 461863805760, 1338408456700, 13177159680000, 33558717136896, 301282248701952, 863701914880000, 6313641012910080, 20863951122979048
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OFFSET
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1,1
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LINKS
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FORMULA
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EXAMPLE
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a(3)=224 because 5^3-1 has divisors {1, 2, 4, 31, 62, 124}.
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MAPLE
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a:=n->numtheory[sigma](5^n-1):
seq(a(n), n=1..100);
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MATHEMATICA
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DivisorSigma[1, 5^Range[30]-1]
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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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