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%I #5 Mar 30 2012 18:50:59
%S 2,4,3,5,1,1,5,2,5,6,5,5,3,2,1,2,5,3,6,6,3,6,3,6,1,2,6,1,5,6,6,6,4,4,
%T 1,6,4,5,6,4,1,1,5,5,2,1,6,3,4,5,6,7,4,6,1,1,6,4,7,6,6,6,3,7,1,2,6,1,
%U 5,2,1,7,6,3,7,1,1,5,3,5,8,5,1,2,4,6,2,1,6,3,6,7,4,7,4,1,2,2,6,1,6,6,2,6,5
%N Number of prime factors in the n-th run of squarefree numbers.
%C a(n) = A001221(A136742(n)) = A001222(A136742(n));
%C a(A136744(n)) = n and a(m) <> n for m < A136744(n).
%H R. Zumkeller, <a href="/A136743/b136743.txt">Table of n, a(n) for n = 1..1000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Squarefree.html">Squarefree</a>
%F a(n) = SUM(A001221(A072284(n)+k): 0<=k < A120992(n)).
%e a(10)=A001221(A136742(10))=A001221(39270)=A001221(2*3*5*7*11*17)=6.
%Y Cf. A005117.
%K nonn
%O 1,1
%A _Reinhard Zumkeller_, Jan 20 2008