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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
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
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Mar 02 2011
STATUS
approved

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Last modified May 22 10:58 EDT 2024. Contains 372745 sequences. (Running on oeis4.)