The ring of quotients of R(S).
The role of semigroups in the elementary theory of numbers
The Schur Theorem for periodic semigroups of Linear relations.
The Schützenberger group of an H-class in the semigroup of binary relations.
The semantical hyperunification problem
A hypersubstitution of a fixed type τ maps n-ary operation symbols of the type to n-ary terms of the type. Such a mapping induces a unique mapping defined on the set of all terms of type t. The kernel of this induced mapping is called the kernel of the hypersubstitution, and it is a fully invariant congruence relation on the (absolutely free) term algebra of the considered type ([2]). If V is a variety of type τ, we consider the composition of the natural homomorphism with the mapping induced...
The semigroup generated by certain operators on the congruence lattice of a Clifford semigroup.
The semigroup of a strongly connected automaton.
The semigroup of circulant Boolean matrices
The semigroup of finite complexes of a group
The semigroup of Fredholm operators.
The semigroup of fully indecomposable relations and Hall relations
The semigroup of Hall relations.
The semigroup of nonempty finite subsets of integers.
The semigroup of nonempty finite subsets of rationals.
The semigroup of semigroup extensions.
The set of minimal distances in Krull monoids
Let H be a Krull monoid with class group G. Then every nonunit a ∈ H can be written as a finite product of atoms, say . The set (a) of all possible factorization lengths k is called the set of lengths of a. If G is finite, then there is a constant M ∈ ℕ such that all sets of lengths are almost arithmetical multiprogressions with bound M and with difference d ∈ Δ*(H), where Δ*(H) denotes the set of minimal distances of H. We show that max Δ*(H) ≤ maxexp(G)-2,(G)-1 and that equality holds if every...
The smallest ideals in the two natural products on ßS.
The structure of bisimple left unipotent semigroups as ordered pairs.
The structure of bisimple orthodox semigroups as ordered pairs.
The structure of certain integrally closed semigroups.