Results 51 to 60 of about 1,383 (108)

Ideal‐Based Quasi Cozero Divisor Graph of a Commutative Ring

open access: yesJournal of Mathematics, Volume 2025, Issue 1, 2025.
Let R be a commutative ring with identity and I be an ideal of R. The zero‐divisor graph of R with respect to I, denoted by ΓI(R), is the graph whose vertices are the set {x ∈ R∖I |xy ∈ I for some y ∈ R∖I} with distinct vertices x and y are adjacent if and only if xy ∈ I.
Faranak Farshadifar, Huadong Su
wiley   +1 more source

2-closures of primitive permutation groups of holomorph type

open access: yesOpen 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
doaj   +1 more source

Existence and Classification of 3‐Regular Symmetric Graphs of Order 6pq With Distinct Primes p and q

open access: yesJournal 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
wiley   +1 more source

Finite groups with star-free noncyclic graphs

open access: yesOpen 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
doaj   +1 more source

Enumerating Problems Concerning Endomorphisms of Double Vertex Wheel Graphs

open access: yesJournal 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
wiley   +1 more source

End-regular and End-orthodox generalized lexicographic products of bipartite graphs

open access: yesOpen 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
doaj   +1 more source

Equivalent Binary Quadratic Form and the Extended Modular Group [PDF]

open access: yes, 2012
Extended modular group $\bar{\Pi}=$, where $ R:z\rightarrow -\bar{z}, \sim T:z\rightarrow\frac{-1}{z},\simU:z\rightarrow\frac{-1}{z +1} $, has been used to study some properties of the binary quadratic forms whose base points lie in the point set ...
malik, M. Aslam, Riaz, Muhammad
core  

Certain Structural Properties for the Direct Product of Cayley Graphs and Their Theoretical Applications

open access: yesJournal of Mathematics, Volume 2024, Issue 1, 2024.
Symmetry properties are of vital importance for graphs. The famous Cayley graph is a good mathematical model as its high symmetry. The normality of the graph can well reflect the symmetry of the graph. In this paper, we characterize the normality of the direct product of Cayley graphs and give a sufficient and necessary condition for the direct product
Li Wang   +3 more
wiley   +1 more source

On finite dual Cayley graphs

open access: yesOpen 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
doaj   +1 more source

Distinguishing Cartesian Products of Countable Graphs

open access: yesDiscussiones 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
doaj   +1 more source

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