cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A126165 Smaller member of each exponential amicable pair.

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%I A126165 #15 May 09 2019 18:34:02
%S A126165 90972,454860,937692,1000692,1182636,1546524,2092356,2638188,2820132,
%T A126165 3365964,3729852,3911796,4275684,4548600,4688460,4821516,5003460,
%U A126165 5367348,5549292,5913180,6095124,6459012,6640956,7186788,7550676,7732620,8096508,8824284,9188172,9370116
%N A126165 Smaller member of each exponential amicable pair.
%C A126165 This sequence includes the smallest member of all exponential amicable pairs and does not discriminate between primitive and nonprimitive pairs.
%H A126165 Amiram Eldar, <a href="/A126165/b126165.txt">Table of n, a(n) for n = 1..10000</a>
%H A126165 Peter Hagis, Jr., <a href="http://dx.doi.org/10.1155/S0161171288000407">Some results concerning exponential divisors</a>, International Journal of Mathematics and Mathematical Sciences, Vol. 11, No. 2, (1988), pp. 343-349.
%H A126165 Ant King, <a href="/A126164/a126164.pdf">Mathematica programs for A126164 - A126166</a>
%H A126165 David Moews, <a href="http://djm.cc/amicable.html">Perfect, amicable and sociable numbers</a>.
%H A126165 J. M. Pedersen, <a href="http://amicable.homepage.dk/knwne2.htm">Known exponential amicable pairs</a>.
%F A126165 The values of m for which esigma(m)=esigma(n)=m+n and m<n, where esigma is defined in A051377.
%e A126165 a(3)=937692 because (937692,968436) is the third exponential amicable pair
%t A126165 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 *)
%Y A126165 Cf. A051377, A054979, A049419, A054980, A126164.
%K A126165 nonn
%O A126165 1,1
%A A126165 _Ant King_, Dec 21 2006
%E A126165 More terms from _Amiram Eldar_, May 09 2019