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%I #12 May 13 2013 01:54:20
%S 0,1,1,1,1,1,1,2,1,1,1,2,1,1,1,1,1,2,1,2,1,1,1,1,1,1,2,2,1,2,1,2,1,1,
%T 1,1,1,1,1,1,1,2,1,2,2,1,1,2,1,2,1,2,1,1,1,1,1,1,1,1,1,1,2,2,1,2,1,2,
%U 1,2,1,2,1,1,2,2,1,2,1,2
%N Number of odd divisors of Omega(n).
%C Omega(n) is the number of prime divisors of n counted with multiplicity, A001222 (also called bigomega(n)).
%C Records are at 2^A053624(n). [_Charles R Greathouse IV_, Jul 29 2011]
%H Charles R Greathouse IV, <a href="/A193509/b193509.txt">Table of n, a(n) for n = 1..10000</a>
%e a(8) = 2 because Omega(8) = 3 and the 2 odd divisors are {1, 3}.
%t f[n_] := Block[{d = Divisors[PrimeOmega[n]]}, Count[OddQ[d], True]]; Table[f[n], {n,80}]
%o (PARI) a(n)=if(n==1,0,my(k=bigomega(n));numdiv(k>>valuation(k,2))) \\ _Charles R Greathouse IV_, Jul 29 2011
%Y Cf. A001222.
%K nonn
%O 1,8
%A _Michel Lagneau_, Jul 29 2011