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A126166
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Larger member of each exponential amicable pair.
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13
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100548, 502740, 968436, 1106028, 1307124, 1709316, 2312604, 2915892, 3116988, 3720276, 4122468, 4323564, 4725756, 5027400, 4842180, 5329044, 5530140, 5932332, 6133428, 6535620, 6736716, 7138908, 7340004, 7943292, 8345484, 8546580, 8948772, 9753156, 10155348
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OFFSET
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1,1
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COMMENTS
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This sequence includes the largest member of all exponential amicable pairs and does not discriminate between primitive and nonprimitive pairs.
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REFERENCES
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Hagis, Peter Jr.; Some Results Concerning Exponential Divisors, Internat. J. Math. & Math. Sci., Vol. 11, No. 2, (1988), pp. 343-350.
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LINKS
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FORMULA
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The values of n 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)= 968436 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, m]], {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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