Results 11 to 20 of about 122 (75)
Quasi‐isometric diversity of marked groups
Journal of Topology, Volume 14, Issue 2, Page 488-503, June 2021., 2021 Abstract We use basic tools of descriptive set theory to prove that a closed set S of marked groups has 2ℵ0 quasi‐isometry classes, provided that every non‐empty open subset of S contains at least two non‐quasi‐isometric groups. It follows that every perfect set of marked groups having a dense subset of finitely presented groups contains 2ℵ0 quasi ...
A. Minasyan, D. Osin, S. Witzel
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Congruences and Hoehnke Radicals on Graphs
Discussiones Mathematicae Graph Theory, 2020 We motivate, introduce, and study radicals on classes of graphs. This concept, and the theory which is developed, imitates the original notion of a Hoehnke radical in universal algebra using congruences.
Broere Izak +2 more
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The structure fault tolerance of burnt pancake networks
Open Mathematics, 2023 One of the symbolic parameters to measure the fault tolerance of a network is its connectivity. The HH-structure connectivity and HH-substructure connectivity extend the classical connectivity and are more practical.
Ge Huifen, Ye Chengfu, Zhang Shumin
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Calculating the virtual cohomological dimension of the automorphism group of a RAAG
Bulletin of the London Mathematical Society, Volume 53, Issue 1, Page 259-273, February 2021., 2021 Abstract We describe an algorithm to find the virtual cohomological dimension of the automorphism group of a right‐angled Artin group. The algorithm works in the relative setting; in particular, it also applies to untwisted automorphism groups and basis‐conjugating automorphism groups.
Matthew B. Day +2 more
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On cospectrality of gain graphs
Special Matrices, 2022 We define GG-cospectrality of two GG-gain graphs (Γ,ψ)\left(\Gamma ,\psi ) and (Γ′,ψ′)\left(\Gamma ^{\prime} ,\psi ^{\prime} ), proving that it is a switching isomorphism invariant.
Cavaleri Matteo, Donno Alfredo
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Open Mathematics, 2020 A Cayley graph Γ\Gamma on a group G is called a dual Cayley graph on G if the left regular representation of G is a subgroup of the automorphism group of Γ\Gamma (note that the right regular representation of G is always an automorphism group of Γ ...
Pan Jiangmin
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Path homology theory of edge-colored graphs
Open Mathematics, 2021 In this paper, we introduce the category and the homotopy category of edge-colored digraphs and construct the functorial homology theory on the foundation of the path homology theory provided by Grigoryan, Muranov, and Shing-Tung Yau.
Muranov Yuri V., Szczepkowska Anna
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Distinguishing Cartesian Products of Countable Graphs
Discussiones Mathematicae Graph Theory, 2017 The distinguishing number D(G) of a graph G is the minimum number of colors needed to color the vertices of G such that the coloring is preserved only by the trivial automorphism.
Estaji Ehsan +4 more
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Finite groups whose intersection power graphs are toroidal and projective-planar
Open Mathematics, 2021 The intersection power graph of a finite group GG is the graph whose vertex set is GG, and two distinct vertices xx and yy are adjacent if either one of xx and yy is the identity element of GG, or ⟨x⟩∩⟨y⟩\langle x\rangle \cap \langle y\rangle is non ...
Li Huani, Ma Xuanlong, Fu Ruiqin
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Finite groups with 4p2q elements of maximal order
Open Mathematics, 2021 It is an interesting and difficult topic to determine the structure of a finite group by the number of elements of maximal order. This topic is related to Thompson’s conjecture, that is, if two finite groups have the same order type and one of them is ...
Tan Sanbiao, Chen Guiyun, Yan Yanxiong
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