This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A134598 #8 Mar 31 2012 13:21:04
%S A134598 1,2,2,2,3,3,3,4,3,3,4,3,4,4,4,2,5,3,4,5,4,4,5,4,4,6,5,4,5,5,5,5,3,5,
%T A134598 6,3,4,5,5,3,6,4,5,6,5,5,6,6,5,4,5,4,7,5,6,5,5,5,6,5,6,7,6,5,6,3,4,6,
%U A134598 6,4,7,3,4,6,5,6,6,5,6,8,4,4,7,4,5,6,6,4,7,6,6,7,6,5,7,3,7,7,6,4,5,5,6,7,5
%N A134598 Duplicate of A080773.
%F A134598 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_2(p_k)}, where ds_2 is the digital sum base 2.
%e A134598 a(6)=3, since 6=2*3 and so a(6)=ds_2(2)+ds_2(3)=1+2.
%K A134598 dead
%O A134598 2,2
%A A134598 _Hieronymus Fischer_, Nov 11 2007