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A129468
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Unitary abundance of n.
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8
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-1, -1, -2, -3, -4, 0, -6, -7, -8, -2, -10, -4, -12, -4, -6, -15, -16, -6, -18, -10, -10, -8, -22, -12, -24, -10, -26, -16, -28, 12, -30, -31, -18, -14, -22, -22, -36, -16, -22, -26, -40, 12, -42, -28, -30, -20, -46, -28, -48, -22, -30, -34, -52, -24
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listen;
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OFFSET
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1,3
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COMMENTS
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The values of n which generate negative elements of this sequence are in A129487, the values of n which generate the zeros of this sequence are in A002827 and the values of n which generate positive elements of this sequence are in A034683
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LINKS
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FORMULA
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EXAMPLE
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As the unitary divisors of 12 are 1, 3, 4 and 12, which sum to 20, then a(12)=20-2x12=-4
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MAPLE
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end proc:
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MATHEMATICA
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UnitaryDivisors[n_Integer?Positive]:=Select[Divisors[n], GCD[ #, n/# ]==1&]; sstar[n_]:=Plus@@UnitaryDivisors[n]-n; sstar[ # ]-#&/@Range[40]
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CROSSREFS
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KEYWORD
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easy,sign
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AUTHOR
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STATUS
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approved
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