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A126165
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Smaller member of each exponential amicable pair.
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12
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90972, 454860, 937692, 1000692, 1182636, 1546524, 2092356, 2638188, 2820132, 3365964, 3729852, 3911796, 4275684, 4548600, 4688460, 4821516, 5003460, 5367348, 5549292, 5913180, 6095124, 6459012, 6640956, 7186788, 7550676, 7732620, 8096508, 8824284, 9188172, 9370116
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OFFSET
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1,1
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COMMENTS
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This sequence includes the smallest member of all exponential amicable pairs and does not discriminate between primitive and nonprimitive pairs.
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LINKS
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FORMULA
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The values of m for which esigma(m)=esigma(n)=m+n and m<n, where esigma is defined in A051377.
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EXAMPLE
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a(3)=937692 because (937692,968436) is the third exponential amicable pair
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MATHEMATICA
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fun[p_, e_] := DivisorSum[e, p^# &]; esigma[1] = 1; esigma[n_] := Times @@ fun @@@ FactorInteger[n]; s = {}; Do[m = esigma[n] - n; If[m > n && esigma[m] - m == n, AppendTo[s, n]], {n, 1, 10^7}]; s (* Amiram Eldar, May 09 2019 *)
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CROSSREFS
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KEYWORD
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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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