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%I #14 Jun 07 2018 02:57:50
%S 1,3,4,7,6,13,8,15,13,23,12,27,14,29,23,31,18,45,20,47,34,49,24,55,31,
%T 55,40,59,30,79,32,63,47,79,47,91,38,85,62,95,42,121,44,99,79,101,48,
%U 111,57,129,71,111,54,145,78,119,91,137,60,159,62,125,103,127,83,167
%N Sum of values when cototient function A051953 is iterated until fixed point is reached.
%H Michael De Vlieger, <a href="/A053480/b053480.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = Sum[Nest[co, n, j], {j, 1, x[n]}]; co[n]=A051953[n], x[n] is the number of iterations
%e If n=130 and A051953 is iterated, we obtain {130,82,42,30,22,12,8,4,2,1,0}. The sum of these terms is 130 + 92 + 42 + 30 + 12 + 8 + 4 + 2 + 1 = 333, so a(130)=333.
%t Array[Total@ Most@ NestWhileList[# - EulerPhi@ # &, #, # > 0 &] &, 66] (* _Michael De Vlieger_, Nov 20 2017 *)
%Y Cf. A051953.
%K nonn
%O 1,2
%A _Labos Elemer_, Jan 14 2000