Results 51 to 60 of about 1,461 (103)
On 7-valent symmetric graphs of order 2pq and 11-valent symmetric graphs of order 4pq
Open Mathematics, 2022 A graph is said to be symmetric if its automorphism group is transitive on its arcs. This article is one of a series of articles devoted to characterizing prime-valent arc-transitive graphs of square-free order or twice square-free order. In this article,
Ling Bo, Lan Ting, Ding Suyun
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Journal of Applied Mathematics, Volume 2025, Issue 1, 2025.This article explores numerous significant additive topological indices based on degrees for linear functional graphs over finite‐dimensional vector spaces. Specifically, we derive some unique topological indices, such as the eccentricity‐based indices and the Wiener index.
Vinnarasi L. +4 more
wiley +1 more source
2-closures of primitive permutation groups of holomorph type
Open Mathematics, 2019 The 2-closure G(2) of a permutation group G on a finite set Ω is the largest subgroup of Sym(Ω) which has the same orbits as G in the induced action on Ω × Ω.
Yu Xue, Pan Jiangmin
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On divisibility graph for simple Zassenhaus groups [PDF]
, 2014 The divisibility graph $D(G)$ for a finite group $G$ is a graph with vertex set $cs~(G)\setminus\{1\}$ where $cs~(G)$ is the set of conjugacy class sizes of $G$. Two vertices $a$ and $b$ are adjacent whenever $a$ divides $b$ or $b$ divides $a$.
A. Abdolghafourian +2 more
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Existence and Classification of 3‐Regular Symmetric Graphs of Order 6pq With Distinct Primes p and q
Journal of Mathematics, Volume 2025, Issue 1, 2025.A graph Σ is said symmetric if its automorphism group acts transitively on the set of its arc. Let p < q be two distinct prime integers. This paper demonstrates that connected 3‐regular symmetric graphs of order 6pq exist if and only if the pair (p, q) belongs to the set (5, 19), (19, 37), (37, 73), which up to isomorphism there are nine sporadic ones,
Mehdi Alaeiyan +3 more
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Finite groups with star-free noncyclic graphs
Open Mathematics, 2019 For a finite noncyclic group G, let Cyc(G) be the set of elements a of G such that 〈a, b〉 is cyclic for each b of G. The noncyclic graph of G is a graph with the vertex set G ∖ Cyc(G), having an edge between two distinct vertices x and y if 〈x, y〉 is not
Ma Xuanlong, Walls Gary L., Wang Kaishun
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Beck's Conjecture for Power Graphs [PDF]
, 2014 Beck's conjecture on coloring of graphs associated to various algebraic objects has generated considerable interest in the community of discrete mathematics and combinatorics since its inception in the year 1988.
Das, Priya, Mukherjee, Himadri
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Enumerating Problems Concerning Endomorphisms of Double Vertex Wheel Graphs
Journal of Mathematics, Volume 2024, Issue 1, 2024.We can define six classes of endomorphisms on a graph, and they always form a chain based on set inclusion. The concepts of endomorphism type and endomorphism spectrum were introduced by Böttcher and Knauer in 1992. They provided a systematic and organized approach to study endomorphisms of graphs.
Yu Li, Hailong Hou, Kaidi Xu, Huadong Su
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Note on the product of the largest and the smallest eigenvalue of a graph
Special MatricesIn this note, we use eigenvalue interlacing to derive an inequality between a graph’s maximum degree and its maximum and minimum adjacency eigenvalues. The equality case is fully characterized.
Abiad Aida +2 more
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End-regular and End-orthodox generalized lexicographic products of bipartite graphs
Open Mathematics, 2016 A graph X is said to be End-regular (End-orthodox) if its endomorphism monoid End(X) is a regular (orthodox) semigroup. In this paper, we determine the End-regular and the End-orthodox generalized lexicographic products of bipartite graphs.
Gu Rui, Hou Hailong
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