Results 51 to 60 of about 590 (104)

opological monoids of almost monotone injective co-finite partial selfmaps of positive integers

Karpatsʹkì Matematičnì Publìkacìï, 2010
In this paper we study the semigroup$mathscr{I}_{infty}^{,Rsh!!!earrow}(mathbb{N})$ of partialco-finite almost monotone bijective transformations of the set ofpositive integers $mathbb{N}$.
Chuchman I.Ya., Gutik O.V.
doaj  

Some generalized metric properties of n-semitopological groups

Algebra universalis
A semitopological group $G$ is called {\it an $n$-semitopological group}, if for any $g\in G$ with $e\not\in\overline{\{g\}}$ there is a neighborhood $W$ of $e$ such that $g\not\in W^{n}$, where $n\in\mathbb{N}$. The class of $n$-semitopological groups ($n\geq 2$) contains the class of paratopological groups and Hausdorff quasi-topological groups.
Lin, Fucai, Qi, Xixi
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Remainders in compactifications of semitopological and paratopological groups

Topology and its Applications, 2014
In this paper, the authors mainly discuss the remainders of semitopological and paratopological groups. The authors show that if the Hausdorff compactification \(bG\) of a non-locally compact semitopological \(G\) has a remainder with a locally a point-countable base, then \(bG\) is separable and metrizable, which gives a positive answer to a question ...
Xie, Li-Hong, Li, Piyu, Lin, Shou
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On the closure of the extended bicyclic semigroup

Karpatsʹkì Matematičnì Publìkacìï, 2011
In the paper we study the semigroup $mathscr{C}_{mathbb{Z}}$which is a generalization of the bicyclic semigroup. We describemain algebraic properties of the semigroup$mathscr{C}_{mathbb{Z}}$ and prove that every non-trivialcongruence $mathfrak{C}$ on the
I. R. Fihel, O. V. Gutik
doaj  

A problem of M. Tkachenko on semitopological groups

Topology and its Applications, 2014
A class \(\mathcal C\) of spaces is a \textit{PS-class} if it contains arbitrary products of its elements, is hereditary with respect to taking subspaces, and contains a one-point space. \textit{M. Tkachenko} in [Topology Appl. 161, 364--376 (2014; Zbl 1287.54047)] defined a \textit{\(\mathcal C\)-reflection} of a semitopological group \(G\), as ...
Lin, Fucai, Zhang, Kexiu
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Cohomology in Grothendieck Topologies and Lower Bounds in Boolean Complexity

, 2005
This paper is motivated by questions such as P vs. NP and other questions in Boolean complexity theory. We describe an approach to attacking such questions with cohomology, and we show that using Grothendieck topologies and other ideas from the ...
Friedman, Joel
core   +1 more source

Some Baire semitopological groups that are topological groups

Topology and its Applications, 2017
A semitopological group is a group equipped with a topology such that the multiplication is separately continuous. The paper contributes to the study of the well-known problem to find topological conditions under which a semitopological group is a topological group. The main result of the author states that a semitopological group which is a regular \(\
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A note on semitopological groups and paratopological groups

Topology and its Applications, 2015
\textit{M. Tkachenko} proved in [Topology Appl. 161, 364--376 (2014; Zbl 1287.54047)] that for every semitopological group \(G\) and every \(i\in\{0,1,2,3,3.5\}\), there exists a continuous homomorphism \(\varphi_{G,i}:G\to H\) onto a \(T_i\)- (resp., \(T_i\) \& \(T_1\)- for \(i\geq3\)) semitopological group \(H\) such that for every continuous mapping
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Regular semitopological groups of every countable sequential order

Topology and its Applications, 1994
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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Semitopological isomorphism of topological groups

, 2004
The author, in a previous paper, has introduced the notion of semitopological isomorphism between topological groups. In the present paper a criterion is given for a continuous isomorphism to be semitopological. It is shown that the property of an isomorphism to be semitopological is preserved by the operations of taking subgroups, quotient groups and ...
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