This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A186989 #7 Mar 30 2012 17:37:34
%S A186989 1,2,4,4,12,4,28,16,32,12,110,16,209,46,69,98,507,57,828,141,277,193,
%T A186989 1591,163,1289,413,1101,441,3785,163,5164,1479,1736,1187,2540,609,
%U A186989 9561,1879,3086,1304,14298,738,18084,3322,3913,3888,25430
%N A186989 Number of subsets of {1, 2, ..., n} containing n and having <=5 pairwise coprime elements.
%H A186989 Alois P. Heinz, <a href="/A186989/b186989.txt">Table of n, a(n) for n = 1..200</a>
%e A186989 a(10) = 12 because there are 12 subsets of {1, 2, ..., 10} containing 10 and having <=5 pairwise coprime elements: {10}, {1,10}, {3,10}, {7,10}, {9,10}, {1,3,10}, {1,7,10}, {1,9,10}, {3,7,10}, {7,9,10}, {1,3,7,10}, {1,7,9,10}. There is no subset with exactly 5 elements here.
%Y A186989 Column 5 of triangle A186975. Sum of A186988 and A186976.
%K A186989 nonn
%O A186989 1,2
%A A186989 _Alois P. Heinz_, Mar 03 2011