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 A079184 #6 Jul 10 2011 18:42:30 %S A079184 0,4,2,2,8,70,3121,2,1,14,22,275,467,48306,178888897 %N A079184 Number of isomorphism classes of non-commutative closed binary operations on a set of order n, listed by class size. %C A079184 A079184(n)+A079185(n)=A079171(n). %C A079184 Elements per row: 1,2,4,8,16,30,... (given by A027423, number of positive divisors of n!) %C A079184 First four rows: 0; 4,2; 2,8,70,3121; 2,1,14,22,275,467,48306,178888897 %C A079184 A079176(x) is equal to the sum of the products of each element in row x of this sequence and the corresponding element of A079210. %C A079184 The sum of each row n is given by A079177(n). %H A079184 C. van den Bosch, <a href="http://cosmos.ucc.ie/~cjvdb1/html/binops.shtml">Closed binary operations on small sets</a> %H A079184 <a href="/index/Gre#groupoids">Index entries for sequences related to groupoids</a> %Y A079184 Cf. A079182, A079183, A079185. %K A079184 nonn,tabf %O A079184 1,2 %A A079184 Christian van den Bosch (cjb(AT)cjb.ie), Jan 03 2003