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 A079193 #7 Mar 30 2012 17:37:12 %S A079193 0,4,3189,178937854,2483527282663335,14325590003288422852078277, %T A079193 50976900301814584087291456618542388746 %N A079193 Number of isomorphism classes of non-associative non-commutative closed binary operations on a set of order n. %C A079193 A079193(n)+A079196(n)+A079199(n)+A001426(n)=A001329(n). %C A079193 Each a(n) is equal to the sum of the elements in row n of A079194. %H A079193 C. van den Bosch, <a href="http://cosmos.ucc.ie/~cjvdb1/html/binops.shtml">Closed binary operations on small sets</a> %H A079193 <a href="/index/Gre#groupoids">Index entries for sequences related to groupoids</a> %Y A079193 Cf. A079192, A079194, A079196, A079199, A001426. %Y A079193 a(n) = A001329(n)-A001425(n)-A027851(n)+A001426(n). %Y A079193 a(n)+A079196(n)+A079199(n)+A001426(n)=A001329(n). %K A079193 nonn %O A079193 1,2 %A A079193 Christian van den Bosch (cjb(AT)cjb.ie), Jan 03 2003 %E A079193 Edited and extended by _Christian G. Bower_, Nov 26 2003