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%I #11 Jan 18 2017 10:35:41
%S 4,9,16,18,25,36,48,50,64,72,80,81,100,112,144,162,180,192,196,200,
%T 208,225,240,252,256,288,289,300,320,324,336,400,432,441,448,450,468,
%U 484,512,576,578,592,624,625,648,676,700,704,720,729,768,784,800,810,832
%N Number of divisors of n is greater than that of sigma[n].
%H Harvey P. Dale, <a href="/A073804/b073804.txt">Table of n, a(n) for n = 1..1000</a>
%F Solutions to A000005(x)>A062068(x)=A000005[A000203(x)]
%e x=25: D[25]={1,5,25},3 divisors; D[sigma(25)]={1,31},2 divisors; 2<3, so 25 is here. x-48:D[48]={1,2,3,4,6,8,12,16,24,48},10 divisors; D[sigma(48)]={1,2,4,31,62,124},6 divisors, 6<10 so 48 is here.
%t Do[s=DivisorSigma[0, DivisorSigma[1, n]]; s0=DivisorSigma[0, n]; If[Greater[s0, s], Print[n]], {n, 1, 1000}]
%t Select[Range[900],DivisorSigma[0,#]>DivisorSigma[0,DivisorSigma[1,#]]&] (* _Harvey P. Dale_, Jan 18 2017 *)
%Y Cf. A000005, A000203, A062068, A073802, A073803, A037197.
%K nonn
%O 1,1
%A _Labos Elemer_, Aug 13 2002
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