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A033856
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Numbers k such that j(k)*phi(k) = sigma(phi(k)), j(k) = A033831(k).
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2
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14, 58, 175, 244, 833, 1017, 1348, 8653, 33263, 33497, 33611, 34099, 34151, 34529, 34771, 36281, 36449, 36743, 37367, 37373, 38311, 38695, 38735, 38915, 39035, 39263, 39295, 39431, 39995, 41015, 41635, 42119, 46209, 46617, 46731, 47067, 49911, 50007, 50871
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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j[n_] := DivisorSum[n, 1&, # > 2 && n/# < #-1 &]; aQ[n_] := j[n]*(p = EulerPhi[ n]) == DivisorSigma[1, p]; Select[Range[10^4], aQ] (* Amiram Eldar, Jul 01 2019 *)
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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