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%I #6 Mar 29 2015 18:44:06
%S 17,19,27,29,31,32,34,35,38,39,40,41,45,47,48,52,54,55,56,58,59,60,62,
%T 69,70,72,75,78,82,84,88,90,92,94,100,110,118,132,138,150,1057,1117,
%U 1153,1201,1237,1241,1261,1271,1301,1313,1321,1333,1349,1351,1359,1381
%N Initial values for f(x)=sigma(phi(x))=A062402(x) such that iteration of f ends in cycle of length=3.
%t f[n_] := DivisorSigma[1, EulerPhi[n]]; g[n_] := Block[{l = NestWhileList[f, n, UnsameQ, All]}, -Subtract @@ Flatten[ Position[l, l[[ -1]]]]]; Select[ Range[ 1396], g[ # ] == 3 &] (* _Robert G. Wilson v_, Jul 23 2004 *)
%Y Cf. A062402, A095953.
%K nonn
%O 1,1
%A _Labos Elemer_, Jul 19 2004
%E Edited and extended by _Robert G. Wilson v_, Jul 23 2004
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