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 A187270 #6 Mar 30 2012 17:37:34
%S A187270 1,3,7,11,23,27,55,71,103,115,231,247,495,543,615,727,1455,1519,3039,
%T A187270 3231,3615,3871,7735,7991,11151,11887,14631,15463,30683,30939,60578,
%U A187270 67646,73813,77845,87284,89054,171020,179960,195265
%N A187270 Number of nonempty subsets of {1, 2, ..., n} with <=9 pairwise coprime elements.
%H A187270 Alois P. Heinz, <a href="/A187270/b187270.txt">Table of n, a(n) for n = 1..200</a>
%F A187270 a(n) = A187262(n,9).
%Y A187270 Column 9 of triangle A187262. First differences are A186993.
%K A187270 nonn
%O A187270 1,2
%A A187270 _Alois P. Heinz_, Mar 07 2011