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A159074 Sum of the k in the range 1<=k<=n such that set of proper divisors of k is not a subset of the set of proper divisors of n. 0

%I #3 Mar 30 2012 19:00:15

%S 1,1,1,1,5,1,11,7,19,24,38,11,50,46,55,67,95,76,113,91,124,150,176,

%T 121,200,221,242,252,306,237

%N Sum of the k in the range 1<=k<=n such that set of proper divisors of k is not a subset of the set of proper divisors of n.

%C The nomenclature of A159072 applies, where the terms in that sum are counted.

%F a(n) = A158976(n) + 1.

%F If p = prime, a(p) = A000217(p) - A158662(p) + 1 = A000217(p) - A014284[A036234(p)] + 1.

%F a(n)+A159073(n)=A000217(n). - R. J. Mathar, Apr 06 2009

%e a(8) = 7 adds k = 6, where {1, 2, 3} is not a subset of the divisor set {1, 2, 4} of n = 8, and k = 1, with an empty proper divisor set.

%Y Cf.: A158976, A000217, A000040, A014284, A036234.

%K nonn

%O 1,5

%A _Jaroslav Krizek_, Apr 04 2009

%E Edited by _R. J. Mathar_, Apr 06 2009

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