A187494 Number of 7-element nondividing subsets of {1, 2, ..., n}.

1, 1, 3, 3, 5, 5, 9, 12, 21, 27, 41, 46, 74, 99, 137, 153, 203, 307, 414, 464, 612, 788, 1126, 1292, 1645, 2039, 2614, 3291, 4120, 5127, 6356, 7180, 9786

Offset

43,3

Comments

A set is called nondividing if no element divides the sum of any nonempty subset of the other elements.

Links

Table of n, a(n) for n=43..75.

Eric Weisstein's World of Mathematics, Nondividing Set

Example

a(43) = 1 because there is one 7-element nondividing subset of {1,2,...,43}: {24,28,31,35,36,40,43}.

Crossrefs

Column 7 of triangle A187489. Cf. A068063.

Sequence in context: A147040 A146277 A050822 * A283843 A241508 A099536

Adjacent sequences: A187491 A187492 A187493 * A187495 A187496 A187497

Keyword

nonn,more

Author

Alois P. Heinz, Mar 10 2011

Status

approved