Search: id:A067740
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%I A067740
%S A067740 1,14,2,6,118740,2915640
%N A067740 a(n) is the smallest number m such that Sigma[m]/Sigma[Phi[m]]=n.
%F A067740 a(n)=Min{x; A000203(x)/A000203[A000010(x)]=n}
%e A067740 n=6, a(6)=2915640, Sigma[2915640]=11793600,Phi[2915640]=608256, Sigma[608256]=1965600 
               and 11793600=6*1965600.
%t A067740 g[x_] := DivisorSigma[1, x]/ DivisorSigma[1, EulerPhi[x]] {m=10, up=200000} 
               a = Table[0, {m} ]; Do[ b = g[n]; If[b < m+1 && a[[b]] == 0, a[[b]] 
               = n], {n, 1, up} ]; a
%Y A067740 Cf. A000203, A000010, A067385.
%Y A067740 Sequence in context: A040194 A107834 A070701 this_sequence A037923 A040195 
               A040189
%Y A067740 Adjacent sequences: A067737 A067738 A067739 this_sequence A067741 A067742 
               A067743
%K A067740 more,nonn
%O A067740 1,2
%A A067740 Labos E. (labos(AT)ana.sote.hu), Jan 29 2002

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