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%I #16 Aug 15 2023 17:01:44
%S 1,6,699
%N Number of submonoids of the monoid of maps from an n-element set to itself.
%H M. Behrisch, <a href="https://doi.org/10.34726/4663">Counting and enumerating transformation monoids</a>, 103rd Workshop on General Algebra (Estonia, 2023).
%H Jannik Hess, <a href="https://pnp.mathematik.uni-stuttgart.de/lexmath/kuenzer/bachelor_hess.pdf">Automorphism groups of monoids acting on number fields</a>, Bachelor Thesis, 2019.
%K bref,hard,nonn,more
%O 1,2
%A _Max Alekseyev_, Jan 27 2022