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%I #3 Mar 30 2012 19:00:15
%S 1,1,1,1,2,1,3,2,4,4,6,2,7,6,7,7,10,7,11,8,11,12,14,8,15,15,16,15,19,
%T 13,20,17,20,21,22,17,25,24,25,21,28,23,29,26,26,30,32,24,33,31,34,33,
%U 37,32,37,33,39,40,42,32,43,42,40,41,45,42,48,45,48,44,51,41,52,51,50,51,54
%N Count of numbers k in the range 1<=k<= n such that set of proper divisors of k is not a subset of the set of the proper divisors of n.
%C Here proper divisors include 1 but not the argument (k or n, respectively) in the divisor set, as defined in A032741.
%C We use the (nonstandard) terminology that the empty set (the proper divisors of 1) is not a subset of another set.
%F a(n)+A159070(n) = n. - _R. J. Mathar_, Apr 06 2009
%e a(8) = 2 counts k=6 with divisors set {1, 2, 3} (not subset of the divisors {1, 2, 4} of n = 8), and k=1 without proper divisors.
%Y Cf.: A158974, A000040, A036234, A000720.
%K nonn
%O 1,5
%A _Jaroslav Krizek_, Apr 04 2009
%E Edited and extended by _R. J. Mathar_, Apr 06 2009
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