%I #15 Oct 27 2019 14:27:37
%S 0,1,2,5,19,84,509,3901,48957
%N Number of self-converse monoids (semigroups with identity) of order n.
%H <a href="/index/Mo#monoids">Index entries for sequences related to monoids</a>
%F a(n) = A058133(n)*2 - A058129(n).
%Y Cf. A058129, A058133.
%K nonn,more
%O 0,3
%A _Christian G. Bower_, Nov 13 2000
%E a(8) from _Max Alekseyev_, Jul 13 2009
%E a(0) prepended by _Jianing Song_, Oct 26 2019
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