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%I #11 Jan 09 2017 06:58:00
%S 0,0,1,1,1,2,3,3,5,5,5,6,7,8,9,9,9,11,13,13,15,15,15,16,16,17,20,21,
%T 22,23,24,24,25,25,26,28,30,32,34,34,34,36,38,38,40,40,40,41,43,43,44,
%U 45,46,49,49,50,53,54,55,56,57,58,61,61,62,63,64,64,65,66,67,69,71,73,74
%N EulerPhi is iterated with initial value n!; a(n) = number of terms that are not powers of 2 among the iterates.
%C Non-powers of 2 arise at the beginning of iteration chains without interruption. Analogous to A053036.
%F a(n) = 1+A053044(n)-A053045(n). - _R. J. Mathar_, Jan 09 2017
%e For n=10, initial value = 3628800; the iteration chain is {3628800, 829440, 221184, 73728, 24576, 8192, 4096, 2048, 1024, 512, 256, 128, 64, 32, 16, 8, 4, 2, 1}. Its length is 19 and the 5 initial values are not powers of 2: 10!, ..., 24576. Thus a(10)=5.
%Y Cf. A000010, A000142, A048855, A053036.
%K nonn
%O 1,6
%A _Labos Elemer_, Feb 25 2000
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