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A126166 Larger member of each exponential amicable pair. 12
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 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
This sequence includes the largest member of all exponential amicable pairs and does not discriminate between primitive and nonprimitive pairs.
REFERENCES
Hagis, Peter Jr.; Some Results Concerning Exponential Divisors, Internat. J. Math. & Math. Sci., Vol. 11, No. 2, (1988), pp. 343-350.
LINKS
Peter Hagis, Jr., Some results concerning exponential divisors, International Journal of Mathematics and Mathematical Sciences, Vol. 11, No. 2, (1988), pp. 343-349.
FORMULA
The values of n for which esigma(m)=esigma(n)=m+n and m<n, where esigma is defined in A051377
EXAMPLE
a(3)= 968436 because (937692,968436) is the third exponential amicable pair
MATHEMATICA
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 *)
CROSSREFS
Sequence in context: A365375 A235901 A251171 * A323754 A251042 A117091
KEYWORD
nonn
AUTHOR
Ant King, Dec 21 2006
EXTENSIONS
Link corrected and reference added by Andrew Lelechenko, Dec 04 2011
More terms from Amiram Eldar, May 09 2019
STATUS
approved

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Last modified March 3 07:26 EST 2024. Contains 370499 sequences. (Running on oeis4.)