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%I #18 Jan 20 2018 17:32:50
%S 1,1,2,3,7,9,20,26,61,82,180,236,594,762
%N Number of conjugacy classes of abelian subgroups of the symmetric group.
%H Liam Naughton, <a href="http://www.maths.nuigalway.ie/~liam/CountingSubgroups.g">CountingSubgroups.g</a>
%H L. Naughton and G. Pfeiffer, <a href="http://arxiv.org/abs/1211.1911">Integer sequences realized by the subgroup pattern of the symmetric group</a>, arXiv:1211.1911 and <a href="https://cs.uwaterloo.ca/journals/JIS/VOL16/Naughton/naughton2.html">J. Int. Seq. 16 (2013) #13.5.8</a>
%H Liam Naughton and Goetz Pfeiffer, <a href="http://schmidt.nuigalway.ie/tomlib/">Tomlib, The GAP table of marks library</a>,
%o (GAP) List(ConjugacyClassesSubgroups(G), x->IsAbelian(Representative(x)));
%K nonn,more
%O 0,3
%A _Liam Naughton_, Nov 09 2012