Factorizable as a finiteness condition.
Filtre sur un monoide fini.
Finite commutative monoids of open maps
Flatness and amalgamation in semigroups.
Four-part semigroups - semigroups of Boolean operations
Four-part semigroups form a new class of semigroups which became important when sets of Boolean operations which are closed under the binary superposition operation f + g := f(g,...,g), were studied. In this paper we describe the lattice of all subsemigroups of an arbitrary four-part semigroup, determine regular and idempotent elements, regular and idempotent subsemigroups, homomorphic images, Green's relations, and prove a representation theorem for four-part semigroups.
Free semigroups and unitary group representations
Function ∪-semigroups
Fundamental order relations on inverse semigroups and on their generalizations.
Fundamental preorders and partial orders on completely [0] simple semigroups.