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%I #15 Dec 04 2017 18:36:14
%S 1,1,1,1,1,1,2,1,2,1,2,1,2,2,1,1,1,2,3,1,2,2,2,1,2,2,3,2,2,1,4,1,2,1,
%T 2,2,3,3,2,1,2,2,4,2,2,2,2,1,4,2,1,2,2,3,2,2,3,2,2,1,4,4,3,1,2,2,4,1,
%U 2,2,4,2,3,3,2,3,4,2,4,1,4,2,2,2,1,4,2,2,2,2,3,2,4,2,3,1,2,4,4,2,3,1,4,2,2
%N Number of odd divisors of phi(n).
%C phi(n) : A000010 is the Euler totient function. This sequence equals A193169 (n) for n < 63.
%H Antti Karttunen, <a href="/A193453/b193453.txt">Table of n, a(n) for n = 1..16384</a>
%F a(n) = A001227(A000010(n)) = A000005(A053575(n)). - _Antti Karttunen_, Dec 04 2017
%e a(63) = 3 because phi(63) = 36 with 3 odd divisors {1, 3, 9}.
%t f[n_] := Block[{d = Divisors[EulerPhi[n]]}, Count[OddQ[d], True]]; Table[f[n], {n, 80}]
%o (PARI) A193453(n) = sumdiv(eulerphi(n), d, d%2); \\ _Antti Karttunen_, Dec 04 2017
%Y Cf. A000010, A001227, A053575.
%K nonn
%O 1,7
%A _Michel Lagneau_, Jul 26 2011
%E More terms from _Antti Karttunen_, Dec 04 2017
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