The intersection of the maximal regular subsemigroups of the semigroup of binary relations.
The inverse semigroup of partial symmetries of a convex polygon.
The largest proper congruence on S(X).
The largest proper regular ideal of
The lattice of congruences on a Baer-Levi semigroup.
The maximal regular ideal of the semigroup of binary relations
The maximal subsemigroups of the ideals of some semigroups of partial injections
We study the structure of the ideals of the semigroup of all isotone (order-preserving) partial injections as well as of the semigroup of all monotone (order-preserving or order-reversing) partial injections on an n-element set. The main result is the characterization of the maximal subsemigroups of the ideals of and .
The monoid of ordered partitions of a natural number.
The monoid of strong endomorphisms of a graph.
The monomorphism semigroup of S(X).
The partially ordered collection of regular ...-classes of S(X).
The pseudovariety of semigroups of triangular matrices over a finite field
We show that semigroups representable by triangular matrices over a fixed finite field form a decidable pseudovariety and provide a finite pseudoidentity basis for it.
The pseudovariety of semigroups of triangular matrices over a finite field
We show that semigroups representable by triangular matrices over a fixed finite field form a decidable pseudovariety and provide a finite pseudoidentity basis for it.
The range order of a product of i transformations from a finite full transformation semigroup.
The Schur Theorem for periodic semigroups of Linear relations.
The semigroup of a strongly connected automaton.
The semigroup of fully indecomposable relations and Hall relations
The structure of the automorphism group of a Croisot-Tessier semigroup.
The structure of the centralizer of a permutation.
The translational hull of a normal cryptogroup