semigroup

Narrow by partially-ordered-set 13 semilattice 13 join-semilattice 11 meet-semilattice 11 mathematical-lattice 10 mathematical-set 5 monoid 5 quasigroup 5 mathematical-group 4 bounded-lattice 2 complete-lattice 2 distributive-lattice 2 abelian-group 1 heyting-algebra 1 totally-ordered-set 1