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%I #9 Jul 15 2021 18:57:59
%S 1,4,33,624,20610,1252032,129552080,63141932606
%N Number of labeled monoids of order n.
%H Eric Postpischil, <a href="http://groups.google.com/groups?&hl=en&lr=&ie=UTF-8&selm=11802%40shlump.nac.dec.com&rnum=2">Posting to sci.math newsgroup, May 21 1990</a>
%H <a href="/index/Mo#monoids">Index entries for sequences related to monoids</a>
%Y a(n) = A058154(n)*n.
%K nonn,more
%O 1,2
%A _Christian G. Bower_, Nov 14 2000
%E a(8) from _Christian G. Bower_, Dec 28 2006