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 A086501 #9 Jul 29 2017 13:30:00 %S A086501 0,0,18,456,13560,510480,25326000,1624815360,131671008000, %T A086501 13168037030400,1593348686899200,229442495919436800, %U A086501 38775787414703539200,7600054444782928128000,1710012252494048735232000 %N A086501 Number of non-commuting permutations: number of ordered pairs g, h in Symm(n) such that gh <> hg, i.e., the subgroup <g,h> is non-Abelian. %F A086501 a(n) = n!^2 - A053529(n) = n! * ( n! - p(n) ) where p(n) is the number of partitions of n (A000041). %Y A086501 Cf. A000041, A053529. %K A086501 nonn %O A086501 1,3 %A A086501 Yuval Dekel (dekelyuval(AT)hotmail.com), Sep 09 2003 %E A086501 More terms from _Ray Chandler_, Sep 17 2003