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A335052
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Odd unitary abundant numbers whose unitary abundancy is closer to 2 than that of any smaller odd unitary abundant number.
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3
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15015, 19635, 21945, 23205, 25935, 31395, 33915, 39585, 41055, 45885, 51765, 80535, 83265, 354585, 359205, 361515, 366135, 382305, 389235, 400785, 403095, 407715, 414645, 416955, 423885, 430815, 437745, 442365, 77967015, 132335385, 617102535, 724239285, 1756753845
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OFFSET
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1,1
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COMMENTS
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The unitary abundancy of a number k is usigma(k)/k, where usigma(k) is the sum of unitary divisors of k (A034448).
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LINKS
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EXAMPLE
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The unitary abundancies of the first terms are 2.148..., 2.112..., 2.099..., 2.085..., 2.072..., ...
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MATHEMATICA
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usigma[1] = 1; usigma[n_] := Times @@ (1 + Power @@@ FactorInteger[n]); seq = {}; r = 3; Do[s = usigma[n]/n; If[s > 2 && s < r, AppendTo[seq, n]; r = s], {n, 1, 10^6, 2}]; seq
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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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