On the ideals of the semigroup of the 1-sphere
On the idempotent ranks of certain semigroups of order-preserving transformations.
On the invariance of small overlap hypotheses.
On the inverse braid and reflection monoids of type .
On the irreducibility of pure difference binomials.
On the Jacobson radical of graded rings.
On the Jacobson radical of graded rings
All commutative semigroups are described such that the Jacobson radical is homogeneous in each ring graded by .
On the kernel of the wreath product of completely simple semigroups.
On the K-theory of the -algebra generated by the left regular representation of an Ore semigroup
We compute the -theory of -algebras generated by the left regular representation of left Ore semigroups satisfying certain regularity conditions. Our result describes the -theory of these semigroup -algebras in terms of the -theory for the reduced group -algebras of certain groups which are typically easier to handle. Then we apply our result to specific semigroups from algebraic number theory.
On the lattice of completely regular monoid varieties.
On the lattice of completely-simple congruences on a Croisot-Tessier semigroup.
On the lattice of congruences on inverse semirings
Let S be a semiring whose additive reduct (S,+) is an inverse semigroup. The relations θ and k, induced by tr and ker (resp.), are congruences on the lattice C(S) of all congruences on S. For ρ ∈ C(S), we have introduced four congruences and on S and showed that and . Different properties of ρθ and ρκ have been considered here. A congruence ρ on S is a Clifford congruence if and only if is a distributive lattice congruence and is a skew-ring congruence on S. If η (σ) is the least distributive...
On the lattice of varieties of completely simple semigroups.
On the least separative congruence on a semigroup.
On the maximal order in and
On the maximal semilattice decomposition of the power semigroup of a semigroup.
On the maximal subsemigroups of the semigroup of all monotone transformations
In this paper we consider the semigroup Mₙ of all monotone transformations on the chain Xₙ under the operation of composition of transformations. First we give a presentation of the semigroup Mₙ and some propositions connected with its structure. Also, we give a description and some properties of the class of all monotone transformations with rank n-1. After that we characterize the maximal subsemigroups of the semigroup Mₙ and the subsemigroups of Mₙ which are maximal in .
On the membership problem for pseudo-varieties of commutative semigroups.
On the monoids of homomorphisms of semigroups with unity
On the multiplicative semi-group of near-rings.