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%I #9 Jan 10 2017 02:30:51
%S 1,2,6,16,48,204,876,3636,18756,105480,561672
%N Number of simple permutations in S_n, i.e., those whose "cycle graph" (or "breakpoint graph") only contains alternating cycles of length at most 3.
%H J.-P. Doignon and A. Labarre, <a href="http://www.cs.uwaterloo.ca/journals/JIS/VOL10/Doignon/doignon77.html">On Hultman Numbers</a>, J. Integer Seq., 10 (2007), 13 pages.
%K nonn,more
%O 1,2
%A _Anthony Labarre_, Nov 21 2007