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.

A123524 Smallest odd number k such that sigma(x)=k has at least n solutions.

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%I A123524 #13 May 21 2025 01:23:55
%S A123524 1,31,347529,10773399,4104665019,28732655133,28732655133,
%T A123524 35492068813383,108695634368139,461396894573979,2529134502772059,
%U A123524 2529134502772059,99414440839732473,175792216832685999,175792216832685999
%N A123524 Smallest odd number k such that sigma(x)=k has at least n solutions.
%C A123524 Note that sigma(x) is odd iff x is in A028982 (numbers of the form m^2 or 2*m^2 for m>0).
%C A123524 a(16) > 10^18. - _Donovan Johnson_, Jun 09 2011
%e A123524 For n=3, sigma(x)=347529 has solutions x = 164836, 203522, 239121.
%Y A123524 Different from A123523.
%K A123524 more,nonn
%O A123524 1,2
%A A123524 _T. D. Noe_, Oct 02 2006
%E A123524 a(8) from _Martin Fuller_, Oct 07 2006
%E A123524 a(9)-a(12) from _Donovan Johnson_, Dec 09 2008
%E A123524 a(13)-a(15) from _Donovan Johnson_, Jun 09 2011