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0, 1, 0, 1, 1, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 1, 0
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OFFSET
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1
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COMMENTS
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If a(k) = 0 for all terms k of A342923, then there cannot be any odd perfect numbers, as k + 3*A003415(k) is odd for any k of the form 4u+2. See comments in A005820 and A235991, also in A347887.
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LINKS
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FORMULA
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MATHEMATICA
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ad[1] = 0; ad[n_] := n * Total@(Last[#]/First[#]& /@ FactorInteger[n]); a[n_] := Mod[ad[DivisorSigma[1, n]], 2]; Array[a, 105] (* Amiram Eldar, Sep 18 2021 *)
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PROG
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(PARI)
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
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CROSSREFS
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Cf. A000035, A000203, A003415, A005820, A165560, A235991, A342923, A342925, A347871, A347887, A349909 (partial sums).
Characteristic function of A347877, while its complement A347878 gives the positions of zeros.
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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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