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%I #8 Oct 21 2017 21:56:34
%S 1,2,3,4,6,14,18,42,90,186,198,210,450,462,930,990,1050,2310,7350,
%T 14910,16170,66990,169050,177870,371910,1540770,2312310,4626930,
%U 4834830,19711230,20030010,30060030,60150090,62852790
%N Numbers n such that phi(phi(n))/n < phi(phi(m))/m for all m < n, where phi is Euler's totient function (A000010).
%t f[n_] := EulerPhi[EulerPhi[n]]/n; a={}; fm=10^10; Do[f1=f[k]; If[f1<fm , fm=f1; AppendTo[a,k]], {k,1,10^6}]; a
%o (PARI) lista(nn) = {my(rmin = 2); for (n=1, nn, if ((r=eulerphi(eulerphi(n))/n) < rmin, rmin = r; print1(n, ", ")););}
%Y Cf. A000010, A010554.
%K nonn,more
%O 1,2
%A _Amiram Eldar_, Oct 15 2017
%E a(26)-a(34) from _Michel Marcus_, Oct 18 2017
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