%I A055037
%S A055037 1,1,1,2,2,3,3,3,4,5,5,5,5,6,7,8,8,8,8,8,9,10,10,11,12,13,13,13,13,13,
%T A055037 13,13,14,15,16,17,17,18,19,20,20,20,20,20,20,21,21,21,22,22,23,23,23,
%U A055037 24,25,26,27,28,28,29,29,30,30,31,32,32,32,32,33,33,33,33,33,34,34,34
%N A055037 Number of numbers <= n with an even number of prime factors (counted 
               with multiplicity).
%H A055037 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               PolyaConjecture.html">Polya Conjecture</a>
%F A055037 1/2*Sum_{k=1..n} (1+lambda(k))= (1/2) *(n+L(n)), where lambda(n)=A008836(n) 
               and L(n)=A002819(n).
%Y A055037 Cf. A001222.
%Y A055037 Sequence in context: A080677 A153112 A005350 this_sequence A125186 A140473 
               A115384
%Y A055037 Adjacent sequences: A055034 A055035 A055036 this_sequence A055038 A055039 
               A055040
%K A055037 nonn
%O A055037 0,4
%A A055037 Antreas P. Hatzipolakis (xpolakis(AT)otenet.gr), Jun 01 2000
%E A055037 Formula and more terms from Vladeta Jovovic (vladeta(AT)eunet.rs), Dec 
               03 2001