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%I #16 Jul 13 2013 12:04:13
%S 1,1,1,2,1,1,1,1,2,1,1,2,1,1,1,2,1,2,1,2,1,1,1,1,2,1,1,2,1,1,1,2,1,1,
%T 1,3,1,1,1,1,1,1,1,2,2,1,1,2,2,2,1,2,1,1,1,1,1,1,1,2,1,1,2,2,1,1,1,2,
%U 1,1,1,2,1,1,2,2,1,1,1,2,2,1,1,2,1,1,1,1,1,2,1,2,1,1,1,2,1,2,2,3
%N Number of odd divisors of tau(n).
%C a(n) = A001227(A000005(n)). [_Reinhard Zumkeller_, Jul 25 2011]
%H Reinhard Zumkeller, <a href="/A193348/b193348.txt">Table of n, a(n) for n = 1..10000</a>
%e a(36) = 3 because tau(36) = 9 and the 3 odd divisors are {1, 3, 9}.
%t f[n_] := Block[{d = Divisors[DivisorSigma[0,n]]}, Count[OddQ[d], True]]; Table[f[n], {n, 80}]
%o (PARI) a(n)=sumdiv(sigma(n,0),d,d%2);
%o (PARI) a(n)=n=numdiv(n);numdiv(n>>valuation(n,2)) \\ _Charles R Greathouse IV_, Jul 30 2011
%Y Cf. A000005.
%K nonn,easy
%O 1,4
%A _Michel Lagneau_, Jul 23 2011
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