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%I #7 Feb 20 2019 21:43:15
%S 0,1,1,2,1,2,1,2,2,3,1,2,1,2,2,4,1,2,1,2,3,4,1,2,2,4,2,4,1,4,1,2,2,4,
%T 2,4,1,2,4,4,1,2,1,2,2,8,1,2,2,3,4,2,1,2,3,2,4,6,1,2,1,4,2,6,2,4,1,4,
%U 2,2,1,4,1,4,2,4,2,4,1,2,4,4,1,6,4,8,8,8,1,6,3,4,6,12,4,4,1,3,4,4,1,6,1,2,4
%N Number of odd divisors in A156552(n): a(1) = 0, for n > 1, a(n) = A001227(A156552(n)) = A000005(A322993(n)).
%H Antti Karttunen, <a href="/A324117/b324117.txt">Table of n, a(n) for n = 1..4473</a>
%H <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>
%F a(1) = 0; for n > 1, a(n) = A000005(A322993(n)) = A000005(A156552(2*A246277(n))) = A324105(2*A246277(n)).
%o (PARI) A064989(n) = {my(f); f = factor(n); if((n>1 && f[1,1]==2), f[1,2] = 0); for (i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f)};
%o A156552(n) = if(1==n, 0, if(!(n%2), 1+(2*A156552(n/2)), 2*A156552(A064989(n))));
%o A246277(n) = { if(1==n, 0, while((n%2), n = A064989(n)); (n/2)); };
%o A322993(n) = A156552(2*A246277(n));
%o A324117(n) = if(1==n, 0, numdiv(A322993(n)));
%Y Cf. A000005, A001227, A156552, A246277, A322813, A322993, A324105, A324115, A324118.
%K nonn
%O 1,4
%A _Antti Karttunen_, Feb 20 2019
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