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%I #4 Mar 31 2012 13:21:04
%S 2,1,4,3,3,3,6,2,5,3,5,3,5,4,8,5,4,3,7,4,5,5,7,6,5,3,7,3,6,3,10,4,7,6,
%T 6,3,5,4,9,5,6,5,7,5,7,5,9,6,8,6,7,7,5,6,9,4,5,5,8,5,5,5,12,6,6,5,9,6,
%U 8,7,8,5,5,7,7,6,6,7,11,4,7,3,8,8,7,4,9,5,7,6,9,4,7,6,11,5,8,5,10,5,8,5,9,7
%N Sum of digital sums (base 3) of the prime factors of n.
%F If p_1*p_2*p_3* ... *p_m=n is the unique prime factorization of n, then a(n)=sum{1<=k<=m, ds_3(p_k)}, where ds_3 is the digital sum base 3.
%e a(6)=3, since 6=2*3 and so a(6)=ds_3(2)+ds_3(3)=2+1.
%Y Cf. A007953, A118503, A080773.
%K nonn,base
%O 2,1
%A _Hieronymus Fischer_, Nov 11 2007
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