%I A067023
%S A067023 1,2,3,4,6,8,9,10,12,15,16,18,20,24,30,36,40,42,48,60,72,80,84,90,96,
%T A067023 120,126,144,168,180,210,240,252,280,288,300,360,420,432,480,504,540,
%U A067023 560,600,630,720,840,900,1008,1080,1260
%N A067023 Sigma-crowded numbers: n such that d(n)/sigma[n] is larger than d(m)/
               sigma[m] for all m>n.
%C A067023 Since d(m)<2sqrt(m)<2sigma[m], we need only test values of m <(2sigma[n]/
               d(n))^2.
%t A067023 crowded[n_] := Module[{}, stop=(2/(dovern=DivisorSigma[0, n]/DivisorSigma[1, 
               n]))^2; For[m=n+1, m<stop, m++, If[DivisorSigma[0, m]/DivisorSigma[1, 
               m] >=dovern, Return[False]]]; True]; Select[Range[1, 13000], crowded]
%Y A067023 An analogue of A066523. Cf. A002182, A000005, A000203, A004394, A034884, 
               A056758.
%Y A067023 Sequence in context: A160719 A085451 A064150 this_sequence A002183 A060306 
               A158614
%Y A067023 Adjacent sequences: A067020 A067021 A067022 this_sequence A067024 A067025 
               A067026
%K A067023 nonn
%O A067023 1,2
%A A067023 Labos E. (labos(AT)ana.sote.hu), Jan 09 2002