Results 41 to 50 of about 90,789 (282)
Comments on the Clique Number of Zero-Divisor Graphs of Zn
Journal of Mathematics, 2022 In 2008, J. Skowronek-kazio´w extended the study of the clique number ωGZn to the zero-divisor graph of the ring Zn, but their result was imperfect. In this paper, we reconsider ωGZn of the ring Zn and give some counterexamples. We propose a constructive
Yanzhao Tian, Lixiang Li
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Prime ideal graphs of commutative rings
Indonesian Journal of Combinatorics, 2022 Let R be a finite commutative ring with identity and P be a prime ideal of R. The vertex set is R - {0} and two distinct vertices are adjacent if their product in P. This graph is called the prime ideal graph of R and denoted by ΓP.
Haval Mohammed Salih, Asaad A. Jund
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Largest reduced neighborhood clique cover number revisited
, 2017 Let $G$ be a graph and $t\ge 0$. The largest reduced neighborhood clique cover number of $G$, denoted by ${\hat\beta}_t(G)$, is the largest, overall $t$-shallow minors $H$ of $G$, of the smallest number of cliques that can cover any closed neighborhood ...
Brown, André EX +11 more
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Saturation numbers for Berge cliques
European Journal of Combinatorics16 pages, 1 ...
English, Sean +3 more
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Small clique number graphs with three trivial critical ideals
Special Matrices, 2018 The critical ideals of a graph are the determinantal ideals of the generalized Laplacian matrix associated to a graph. Previously, they have been used in the understanding and characterizing of the graphs with critical group with few invariant factors ...
Alfaro Carlos A., Valencia Carlos E.
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On General Reduced Second Zagreb Index of Graphs
Mathematics, 2022 Graph-based molecular structure descriptors (often called “topological indices”) are useful for modeling the physical and chemical properties of molecules, designing pharmacologically active compounds, detecting environmentally hazardous substances, etc.
Lkhagva Buyantogtokh +2 more
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Ideal based graph structures for commutative rings
Cubo, 2022 We introduce a graph structure $\gamrr$ for commutative rings with unity. We study some of the properties of the graph $\gamrr$. Also we study some parameters of $\gamrr$ and find rings for which $\gamrr$ is split.
M. I. Jinnah, Shine C. Mathew
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On the choosability of claw-free perfect graphs
, 2015 It has been conjectured that for every claw-free graph $G$ the choice number of $G$ is equal to its chromatic number. We focus on the special case of this conjecture where $G$ is perfect.
Gravier, Sylvain +2 more
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Bounds on the Clique and the Independence Number for Certain Classes of Graphs
MathematicsIn this paper, we study the class of graphs Gm,n that have the same degree sequence as two disjoint cliques Km and Kn, as well as the class G¯m,n of the complements of such graphs.
Valentin E. Brimkov, Reneta P. Barneva
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A Different Short Proof of Brooks’ Theorem
Discussiones Mathematicae Graph Theory, 2014 Lovász gave a short proof of Brooks’ theorem by coloring greedily in a good order. We give a different short proof by reducing to the cubic case.
Rabern Landon
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