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%I #13 Jan 14 2014 04:38:16
%S 1,1,1,2,2,1,2,4,2,4,2,3,2,4,4,8,2,4,4,16,4,4,2,12,6,4,8,16,2,16,4,16,
%T 4,4,8,32,8,8,4,64,4,16,2,32,16,8,2,48,8,48,4,16,4,32,16,96,16,8,4,
%U 192,4,8,16,64,8,16,8,32,16,128,4,256,4,16,24,32
%N Number of odd divisors of Fibonacci(n).
%H Charles R Greathouse IV, <a href="/A193292/b193292.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = A001227(A000045(n)). - _Michel Marcus_, Jan 14 2014
%e a(16) = 8 because Fibonacci(16) = 987 = 3 * 7 * 47 and the 8 odd divisors are {1, 3, 7, 21, 47, 141, 329, 987}.
%t f[n_] := Block[{d = Divisors[Fibonacci[n]]}, Count[OddQ[d], True]]; Table[
%t f[n], {n, 110}]
%o (PARI) a(n)=n=fibonacci(n);numdiv(n>>valuation(n,2)) \\ _Charles R Greathouse IV_, Jul 30 2011
%Y Cf. A000045, A193291.
%K nonn
%O 1,4
%A _Michel Lagneau_, Jul 21 2011
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