Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #3 Mar 30 2012 18:50:43
%S 0,0,0,1,1,2,2,2,2,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,6,7,7,7,7,7,7,7,8,
%T 8,8,8,9,9,9,9,9,9,9,10,11,11,11,11,11,11,11,11,11,11,11,11,12,12,12,
%U 12,13,14,14,14,14,14,14,14,14,14,14,14,15,16,16,16,16,16,16,16,17,17
%N Number of numbers <= n having exactly as many prime factors as the value of their smallest prime factor.
%C a(n) = #{m: A001222(m)=A020639(m), m<=n};
%C A091372(n) + a(n) + A091374(n) = n.
%Y Cf. A091376, A091371.
%K nonn
%O 1,6
%A _Reinhard Zumkeller_, Jan 04 2004