A159072 -id:A159072

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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
0

1, 1, 1, 1, 5, 1, 11, 7, 19, 24, 38, 11, 50, 46, 55, 67, 95, 76, 113, 91, 124, 150, 176, 121, 200, 221, 242, 252, 306, 237

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OFFSET

1,5

COMMENTS

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

LINKS

FORMULA

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

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

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

EXAMPLE

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.

CROSSREFS

KEYWORD

nonn

AUTHOR

EXTENSIONS

Edited by R. J. Mathar, Apr 06 2009

STATUS

approved

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