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 A239763 #9 Jul 18 2014 12:38:24 %S A239763 1,1,10,171,4600,168285,7988736,472245991 %N A239763 Number of pairs of functions (f,g) from a set of n elements into itself satisfying f(f(x)) = f(g(x)). %Y A239763 Cf. A181162. %K A239763 nonn,more %O A239763 0,3 %A A239763 _Chad Brewbaker_, Mar 26 2014 %E A239763 a(6)-a(7) from _Giovanni Resta_, Mar 28 2014