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%I #11 May 30 2018 03:53:01
%S 1,2,4,6,12,11,25,22,32,26,54,55,67,68,85,117,126,113,150,166,130,178,
%T 186,207,201,194,253,255,256,295,284,309,320,315,348,347,365,398,423,
%U 425,433,459,468,488
%N When cototient function (A051953) is iterated with initial value A002110(n), a(n) = number of iterates that are not powers of 2.
%C In these iteration chains, the numbers that are not powers of 2 seem to be in the majority.
%e n=6, A002110(6)=30030; the corresponding iteration chain is: {30030, 24270, 17806, 9238, 4798, 2400, 1760, 1120, 736, 384, 256, 128, 64, 32, 16, 8, 4, 2, 1, 0}. It has 20 terms, among which entries from the first to 10th, also the last 0, are not powers of 2, so a(6)=11.
%Y Cf. A002110, A051953.
%K more,nonn
%O 1,2
%A _Labos Elemer_, Feb 28 2000
%E a(13)-a(44) from _Donovan Johnson_, May 13 2010