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A216897
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a(n) = smallest m such that sigma(m)/m = n + 1/3.
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0
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OFFSET
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1,1
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COMMENTS
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An upper bound for a(7) is a 77-digit number with factorization: 2^35 3^20 5^9 7^3 11 13^2 17 19 23 29 31 37^2 41 61 67 71 73 109 137 409 521 547 1093 36809 368089.
An upper bound for a(8) is a 165-digit number that can be found on given link where line begins with 25/3.
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LINKS
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EXAMPLE
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a(1) = 3 because sigma(3)/3 = 4/3 = 1 + 1/3 and 3 is the earliest m such that sigma(m)/m = 1 + 1/3.
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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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