%I #8 Mar 29 2020 02:11:45
%S 0,1,3,6,10,3,9,6,14,10,20,9,21,9,14,29,45,14,32,21,21,20,42,9,33,21,
%T 45,32,60,14,44,29,41,45,33,33,69,32,33,21,61,21,63,44,61,42,88,44,92,
%U 33,61,69,121,45,61,32,69,60,118,33,93,44,92,106,92,41,107
%N Sum of the iterated infinitary totient function iphi (A091732).
%H Amiram Eldar, <a href="/A333611/b333611.txt">Table of n, a(n) for n = 1..10000</a>
%e a(3) = iphi(3) + iphi(iphi(3)) = 2 + 1 = 3.
%t f[p_, e_] := p^(2^(-1 + Position[Reverse @ IntegerDigits[e, 2], 1])); iphi[1] = 1; iphi[n_] := Times @@ (Flatten@(f @@@ FactorInteger[n]) - 1); a[n_] := Plus @@ NestWhileList[iphi, n, # != 1 &] - n; Array[a, 100]
%Y Cf. A091732, A092693, A329153, A330273, A331273, A333609.
%K nonn
%O 1,3
%A _Amiram Eldar_, Mar 28 2020
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