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%I #9 Jul 29 2017 13:30:00
%S 0,0,18,456,13560,510480,25326000,1624815360,131671008000,
%T 13168037030400,1593348686899200,229442495919436800,
%U 38775787414703539200,7600054444782928128000,1710012252494048735232000
%N 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 a(n) = n!^2 - A053529(n) = n! * ( n! - p(n) ) where p(n) is the number of partitions of n (A000041).
%Y Cf. A000041, A053529.
%K nonn
%O 1,3
%A Yuval Dekel (dekelyuval(AT)hotmail.com), Sep 09 2003
%E More terms from _Ray Chandler_, Sep 17 2003