Topic
Cancellative semigroup
About: Cancellative semigroup is a research topic. Over the lifetime, 1320 publications have been published within this topic receiving 13319 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: In this article, the conditions générales d'utilisation (http://www.numdam.org/legal.cedram.php) of the agreement are discussed.
Abstract: © Université Bordeaux 1, 1991, tous droits réservés. L’accès aux archives de la revue « Journal de Théorie des Nombres de Bordeaux » (http://jtnb.cedram.org/) implique l’accord avec les conditions générales d’utilisation (http://www.numdam.org/legal.php). Toute utilisation commerciale ou impression systématique est constitutive d’une infraction pénale. Toute copie ou impression de ce fichier doit contenir la présente mention de copyright.
39 citations
TL;DR: A semigroup S (with zero) is called a right inverse semigroup if every (nonnull) principal left ideal of S has a unique idempotent generator as discussed by the authors.
39 citations
TL;DR: In this article, the smallest ideal of (0+,+), its closure, and those sets "central" in (0++), that is, those sets which are members of minimal idempotents in ( 0+, +), are characterized.
Abstract: of ultrafiliters on (0,1) that converge to 0 is a semigroup under the restriction of the usual operation + on BetaR
d
, the Stone-Cech compactification of the discrete semigroup (R
d
,+). It is also a subsemigroup of Beta((0,1)
d
,·). The interaction of these operations has recently yielded some strong results in Ramsey Theory. Since (0+,·) is an ideal of Beta((0,1)
d
,·), much is known about the structure of (0+,·). On the other hand, (0+,+) is far from being an ideal of (BetaR
d
,+) so little about its algebraic structure follows from known results. We characterize here the smallest ideal of (0+,+), its closure, and those sets "central" in (0+,+), that is, those sets which are members of minimal idempotents in (0+, +). We derive new combinatorial applications of those sets that are central in (0+,+).
38 citations
TL;DR: The behavior of strongly continuous one-parameter semigroups of operators on locally convex spaces is considered in this paper, where the emphasis is placed on semigroup that grow too rapidly to be treated by classical Laplace transform methods.
38 citations
Journal Article•
TL;DR: In this article, it was shown that if G satisfies an algebraic condition, which is true for all abelian semigroups, then there exists a K-quasiconformal homeomorphism of U onto an open set V such that all the functions in G are meromorphic functions of V into itself.
Abstract: Let G be a semigroup of K-quasiregular or K-quasimeromorphic functions map- ping a given open set U in the Riemann sphere into itself, for a fixed K, the semigroup operation being the composition of functions. We prove that if G satisfies an algebraic condition, which is true for all abelian semigroups, then there exists a K-quasiconformal homeomorphism of U onto an open set V such that all the functions in f ◦G◦f −1 are meromorphic functions of V into itself. In particular, if U is the whole sphere then the elements of f ◦G ◦f −1 are rational functions. We give an example of a semigroup generated by two functions on the sphere, each quasiconformally conjugate to a quadratic polynomial, that cannot be quasiconformally conjugated to a semigroup of rational functions. We give another such example of a semigroup of K-quasiconformal homeo- morphisms. These results extend and complement a similar positive conjugacy result of Tukia and of Sullivan for groups of K-quasiconformal homeomorphisms.
37 citations