%I #5 Oct 15 2013 22:31:29
%S 195938,224450,13645088,15870978,18180450,29184800,1105252128,
%T 2363968800,2686005218,2917410498,3564550178,5056357922,8442721568,
%U 10814792450,18587462432,21292224800,48666384162,140836104992
%N Solutions to sigma[2*(x^2)]=odd^2.
%e m=195938=2.313.313 and sigma[195938]=294849=543.543 and 543=3.181 odd nonprime. No odd prime solutions were found below 10^12.
%t Do[s=DivisorSigma[1, 2*(n^2)]; If[IntegerQ[Sqrt[s]]&&Mod[s, 2]==1, Print[2*(n^2)]], {n, 1, 10000000}]
%Y Cf. A000203, A001248, A028982, A074386.
%K nonn
%O 1,1
%A _Labos Elemer_, Aug 22 2002
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