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 A239838 #19 Mar 12 2015 12:13:11 %S A239838 1,1,2,12,96,600,9360,146160,1935360,41368320,1092268800,23111827200, %T A239838 700300339200,26141033318400,810322216704000,31624796915712000, %U A239838 1537594906079232000,63980698878480384000,3128302230597992448000,187447679378885173248000 %N A239838 Number of ordered pairs of permutation functions on n elements where f(f(f(x))) = g(g(g(x))). %H A239838 Hiroaki Yamanouchi, <a href="/A239838/b239838.txt">Table of n, a(n) for n = 0..60</a> %H A239838 Hiroaki Yamanouchi, <a href="/A239838/a239838.py.txt">Python code</a> %Y A239838 Cf. A000012, A000085, A000142, A088311, A053529, A001044. %Y A239838 a(n) = n! * A232207(n) for n>0. - _Alois P. Heinz_, Jul 23 2014 %K A239838 nonn %O A239838 0,3 %A A239838 _Chad Brewbaker_, Mar 27 2014 %E A239838 a(8)-a(12) from _Giovanni Resta_, Mar 27 2014 %E A239838 a(13) from _Alois P. Heinz_, Jul 23 2014 %E A239838 a(14)-a(19) from _Hiroaki Yamanouchi_, Mar 12 2015