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 A186986 Number of 10-element subsets of {1, 2, ..., n} having pairwise coprime elements. 3

%I

%S 8,8,16,16,24,24,268,268,1569,1857,1952,2010,2156,2176,9265,9596,

%T 10167,10339,35489,35589,103267,107303,111153,115675,297827,301611,

%U 442057,451649,484539,503173,1150127,1164141,1290703,1320491,1413885,1471627

%N Number of 10-element subsets of {1, 2, ..., n} having pairwise coprime elements.

%H Alois P. Heinz, <a href="/A186986/b186986.txt">Table of n, a(n) for n = 23..200</a>

%e 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}.

%Y Column 10 of triangle A186974. Partial sums of A186981.

%K nonn

%O 23,1

%A _Alois P. Heinz_, Mar 02 2011

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Last modified September 17 12:00 EDT 2021. Contains 347477 sequences. (Running on oeis4.)