Results 21 to 26 of about 26 (26)
On weaker forms of compactness Lindelöfness and countable compactness
International Journal of Mathematics and Mathematical Sciences, Volume 13, Issue 1, Page 55-59, 1990., 1988 A theory of e‐countable compactness and e‐Lindelöfness which are weaker than the concepts of countable compactness and Lindelöfness respectively is developed. Amongst other results we show that an e‐countably compact space is pseudocompact, and an example of a space which is pseudocompact but not e‐countably compact with respect to any dense set is ...
D. Baboolal, J. Backhouse, R. G. Ori
wiley +1 more source
Applications of δ‐Open Sets via Separation Axioms, Covering Properties, and Rough Set Models
Journal of Mathematics, Volume 2025, Issue 1, 2025.In this article, we make use of δ‐open sets to establish some topological concepts related to separation axioms and covering properties and to propose novel topological rough set models. We first demonstrate that the classes of regular‐open and δ‐open subsets of a finite topological space are equivalent when this space has the property of ∂(A)∩∂(B)⊆∂(A
Tareq M. Al-Shami +2 more
wiley +1 more source
International Journal of Mathematics and Mathematical Sciences, Volume 13, Issue 3, Page 507-512, 1990., 1989 An ideal on a set X is a nonempty collection of subsets of X closed under the operations of subset (heredity) and finite unions (additivity). Given a topological space (X, τ) an ideal ℐ on X and A⊆X, ψ(A) is defined as ⋃{U ∈ τ : U − A ∈ ℐ}. A topology, denoted τ*, finer than τ is generated by the basis {U − I : U ∈ τ, I ∈ ℐ}, and a topology, denoted 〈ψ(
T. R. Hamlett, David Rose
wiley +1 more source
A topological property of β(N)
International Journal of Mathematics and Mathematical Sciences, Volume 3, Issue 4, Page 713-717, 1980., 1980 In this paper we prove that the Stone‐Cech‐compactification of the natural numbers does not admit a countable infinite decomposition into subsets homeomorphic to each other and to the said compactification.
Anastase Nakassis
wiley +1 more source
Group reflection and precompact paratopological groups
Topological Algebra and its Applications, 2013 Tkachenko Mikhail
doaj +1 more source
Boolean algebras admitting a countable minimally acting group
Open Mathematics, 2014 Błaszczyk Aleksander +2 more
doaj +1 more source