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%I #7 Mar 30 2012 17:37:34
%S 6,6,39,41,44,56,213,219,619,655,731,777,1853,1909,2775,2961,3707,
%T 3923,7803,7859,14308,15876,17437,18459,20865,21313,36080,38103,41568,
%U 42828,68688,69360,106470,111456,117033,122883,181854,185066,230208,236610
%N Number of 6-element subsets of {1, 2, ..., n} having pairwise coprime elements.
%H Alois P. Heinz, <a href="/A186982/b186982.txt">Table of n, a(n) for n = 11..200</a>
%e a(12) = 6 because there are 6 6-element subsets of {1, 2, ..., 12} having pairwise coprime elements: {1,2,3,5,7,11}, {1,5,7,8,9,11}, {1,4,5,7,9,11}, {1,3,5,7,8,11}, {1,3,4,5,7,11}, {1,2,5,7,9,11}.
%Y Column 6 of triangle A186974. Partial sums of A186977.
%K nonn
%O 11,1
%A _Alois P. Heinz_, Mar 02 2011
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