Results 61 to 70 of about 328 (159)
Journal of the London Mathematical Society, Volume 113, Issue 1, January 2026.Abstract In 1935, Philip Hall published what is often referred to as ‘Hall's marriage theorem’ in a short paper (P. Hall, J. Lond. Math. Soc. (1) 10 (1935), no. 1, 26–30.) This paper has been very influential. I state the theorem and outline Hall's proof, together with some equivalent (or stronger) earlier results, and proceed to discuss some the many ...
Peter J. Cameron
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Absolutely strongly star-Menger spaces
Topology and its Applications, 2013 Abstract A space X is absolutely strongly star-Menger if for each sequence ( U n : n ∈ N ) of open covers of X and each dense subset D of X, there exists a sequence ( F n : n ∈ N ) of finite subsets of D such that { St ( F n , U n ) : n ∈ N } is an open cover of X.
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Indestructibly productively Lindelöf and Menger function spaces
Topology and its Applications, 2020 For a Tychonoff space $X$ and a family $ $ of subsets of $X$, we denote by $C_ (X)$ the $T_1$-space of all real-valued continuous functions on $X$ with the $ $ -open topology. A topological space is productively Lindel f if its product with every Lindel f space is Lindel f.
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Computational and Mathematical Methods, Volume 2026, Issue 1, 2026.In this article, several new fixed point results are established by employing the Krasnoselskii iteration method for a pair of self‐mappings in Banach spaces. It explores the idea of enriched contraction, conditionally sequential absorbing mappings, and various types of continuity terms. Further, to support our main result, an example is provided which
Priya Goel +4 more
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New dynamic fixed point results in Menger spaces [PDF]
Surveys in Mathematics and its Applications, 2023 The objective of this paper is to generalize and improve some results in fixed point theorems in both complete metric space and Menger space. These results are generalizations of the analogous ones recently proved by Khojasteh [5], Demma [1], Yildirim ...
Besma Laouadi +4 more
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Angewandte Chemie, Volume 137, Issue 51, December 15, 2025.Es wurden zwei Reihen von C2‐terphenylierten Derivaten von drei N‐heterocyclischen Carbenen (NHCs) untersucht. Die para‐terphenylierten Spezies weisen drei stabile (reversible) Redoxzustände auf (z. B. [2b]⁺, [2b]● und [2b]−), während bei den meta‐terphenylierten Derivaten nur die kationischen und neutralen Zustände (d. h.
Henric Steffenfauseweh +5 more
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Families of quasi-pseudo-metrics generated by probabilistic quasi-pseudo-metric spaces [PDF]
Surveys in Mathematics and its Applications, 2007 This paper contains a study of families of quasi-pseudo-metrics (the concept of a quasi-pseudo-metric was introduced by Wilson, Albert and Kelly) generated by probabilistic quasi-pseudo-metric-spaces which are generalization of probabilistic metric ...
Mariusz T. Grabiec +2 more
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Convexity and Geodesic Metric Spaces
پژوهشهای ریاضی, 2021 In this paper, we first present a preliminary study on metric segments and geodesics in metric spaces. Then we recall the concept of d-convexity of sets and functions in the sense of Menger and study some properties of d-convex sets and d-convex ...
Sajad Ranjbar +2 more
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Counterexamples Regarding Linked and Lean Tree‐Decompositions of Infinite Graphs
Journal of Graph Theory, Volume 110, Issue 4, Page 398-407, December 2025.ABSTRACT Kříž and Thomas showed that every (finite or infinite) graph of tree‐width k ∈ N admits a lean tree‐decomposition of width k. We discuss a number of counterexamples demonstrating the limits of possible generalisations of their result to arbitrary infinite tree‐width.
Sandra Albrechtsen +3 more
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Weakly compatible maps in 2-non-Archimedean Menger PM-spaces
International Journal of Mathematics and Mathematical Sciences, 2002 The aim of this paper is to introduce the concept of weakly compatible maps in 2-non-Archimedean Menger probabilistic metric (PM) spaces and to prove a theorem for these mappings without appeal to continuity. We also provide an application.
Renu Chugh, Sanjay Kumar
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