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A366653
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Sum of the divisors of 8^n-1.
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12
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8, 104, 592, 8736, 38912, 473600, 2466048, 38054016, 155493536, 2015330304, 10359014400, 166290432000, 636328345600, 7645340651520, 42424026529792, 648494317126656, 2599936977797120, 32817383473149440, 164708609085669376, 3010983668199456768
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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(5)=38912 because 8^5-1 has divisors {1, 7, 31, 151, 217, 1057, 4681, 32767}.
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MAPLE
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a:=n->numtheory[sigma](8^n-1):
seq(a(n), n=1..100);
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MATHEMATICA
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DivisorSigma[1, 8^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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