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A187550
Number of 8-element nondividing subsets of {1, 2, ..., n}.
1
2, 3, 4, 5, 6, 9, 12, 15, 19, 24, 35, 46, 60, 83, 102, 135
OFFSET
65,1
COMMENTS
A set is called nondividing if no element divides the sum of any nonempty subset of the other elements.
LINKS
Eric Weisstein's World of Mathematics, Nondividing Set
EXAMPLE
a(65) = 2 because there are two 8-element nondividing subsets of {1,2,...,65}: {36,40,48,49,53,61,64,65}, {30,44,45,49,50,59,64,65}.
CROSSREFS
Column 8 of triangle A187489. Cf. A068063.
Sequence in context: A036032 A008813 A133463 * A307818 A358033 A057492
KEYWORD
nonn,more
AUTHOR
Alois P. Heinz, Mar 11 2011
STATUS
approved