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%I #6 Mar 30 2012 17:37:11
%S 1,1,1,3,12,68,502,4158
%N Number of asymmetric idempotent semigroups of order n.
%H <a href="/index/Se#semigroups">Index entries for sequences related to semigroups</a>
%Y Main diagonal of A058113.
%K nonn,hard
%O 0,4
%A _Christian G. Bower_, Nov 09 2000
%E Updated Feb 19 2001