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A187493 Number of 6-element nondividing subsets of {1, 2, ..., n}. 1
1, 3, 4, 7, 15, 27, 45, 55, 85, 133, 199, 262, 378, 534, 803, 999, 1319, 1742, 2309, 3007, 4020, 5166, 6565, 7950, 10380, 12882, 16533, 19664, 24099, 30912, 37550, 44092, 54465, 65117, 79616, 94144, 111780, 132592, 159228, 187506, 219949, 256514 (list; graph; refs; listen; history; text; internal format)
OFFSET

31,2

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=31..72.

Eric Weisstein's World of Mathematics, Nondividing Set

EXAMPLE

a(31) = 1 because there is one 6-element nondividing subset of {1,2,...,31}: {16,19,23,24,28,31}.

CROSSREFS

Column 6 of triangle A187489. Cf. A068063.

Sequence in context: A219277 A024368 A329666 * A027020 A130755 A286348

Adjacent sequences:  A187490 A187491 A187492 * A187494 A187495 A187496

KEYWORD

nonn

AUTHOR

Alois P. Heinz, Mar 10 2011

STATUS

approved

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Last modified June 28 21:04 EDT 2022. Contains 354907 sequences. (Running on oeis4.)