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A186986 Number of 10-element subsets of {1, 2, ..., n} having pairwise coprime elements. 3
8, 8, 16, 16, 24, 24, 268, 268, 1569, 1857, 1952, 2010, 2156, 2176, 9265, 9596, 10167, 10339, 35489, 35589, 103267, 107303, 111153, 115675, 297827, 301611, 442057, 451649, 484539, 503173, 1150127, 1164141, 1290703, 1320491, 1413885, 1471627 (list; graph; refs; listen; history; text; internal format)
OFFSET

23,1

LINKS

Alois P. Heinz, Table of n, a(n) for n = 23..200

EXAMPLE

a(24) = 8 because there are 8 10-element subsets of {1, 2, ..., 24} having pairwise coprime elements: {1,2,3,5,7,11,13,17,19,23}, {1,2,5,7,9,11,13,17,19,23}, {1,3,4,5,7,11,13,17,19,23}, {1,3,5,7,8,11,13,17,19,23}, {1,3,5,7,11,13,16,17,19,23}, {1,4,5,7,9,11,13,17,19,23}, {1,5,7,8,9,11,13,17,19,23}, {1,5,7,9,11,13,16,17,19,23}.

CROSSREFS

Column 10 of triangle A186974. Partial sums of A186981.

Sequence in context: A205709 A028997 A168397 * A112439 A309461 A245420

Adjacent sequences:  A186983 A186984 A186985 * A186987 A186988 A186989

KEYWORD

nonn

AUTHOR

Alois P. Heinz, Mar 02 2011

STATUS

approved

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Last modified July 31 22:33 EDT 2021. Contains 346377 sequences. (Running on oeis4.)