Inverse semigroup varieties generated by E-unitary semigroups.
Inverse semigroup varieties with the amalgamation property.
Inverse semigroups determined by their lattices of inverse subsemigroups
Irreducibility of ideals in a one-dimensional analytically irreducible ring
Let be a one-dimensional analytically irreducible ring and let be an integral ideal of . We study the relation between the irreducibility of the ideal in and the irreducibility of the corresponding semigroup ideal . It turns out that if is irreducible, then is irreducible, but the converse does not hold in general. We collect some known results taken from [5], [4], [3] to obtain this result, which is new. We finally give an algorithm to compute the components of an irredundant decomposition...
Irreducible Belousov equations on quasigroups
Irreducible semigroups are monotone.
Is minimal group congruence smallest?
Is Topologically Simple Simple?
Isolated subsemigroups in the variants of .
Isomorphisms of products
Isomorphisms of products of infinite graphs
Isomorphisms of products of weakly homogeneous spaces
Isomorphisms of semigroups of transformations.
Isomorphisms of wreath products of monoids.
Isomorphisms of wreath products of monoids, I.
Isotopy invariant quasigroup identities
According to S. Krstić, there are only four quadratic varieties which are closed under isotopy. We give a simple procedure generating quadratic identities and deciding which of the four varieties they define. There are about 37000 such identities with up to five variables.
Joins and meets of congruences on a regular semigroup.
Joint subnormality of n-tuples and C₀-semigroups of composition operators on L²-spaces
Joint subnormality of a family of composition operators on L²-space is characterized by means of positive definiteness of appropriate Radon-Nikodym derivatives. Next, simplified positive definiteness conditions guaranteeing joint subnormality of a C₀-semigroup of composition operators are supplied. Finally, the Radon-Nikodym derivatives associated to a jointly subnormal C₀-semigroup of composition operators are shown to be the Laplace transforms of probability measures (modulo a C₀-group of scalars)...
Joint subnormality of n-tuples and C₀-semigroups of composition operators on L²-spaces, II
In the previous paper, we have characterized (joint) subnormality of a C₀-semigroup of composition operators on L²-space by positive definiteness of the Radon-Nikodym derivatives attached to it at each rational point. In the present paper, we show that in the case of C₀-groups of composition operators on L²-space the positive definiteness requirement can be replaced by a kind of consistency condition which seems to be simpler to work with. It turns out that the consistency condition also characterizes...
Kommutative Teilhabgruppen der Kompositionshalbgruppe von Polynomen und formalen Potenzreihen.