Results 41 to 50 of about 8,457 (169)
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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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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Lower bounds on the signed (total) $k$-domination number depending on the clique number
Communications in Combinatorics and Optimization, 2018 Let $G$ be a graph with vertex set $V(G)$. For any integer $k\ge 1$, a signed (total) $k$-dominating function is a function $f: V(G) \rightarrow \{ -1, 1\}$ satisfying $\sum_{x\in N[v]}f(x)\ge k$ ($\sum_{x\in N(v)}f(x)\ge k$) for every $v ...
L. Volkmann
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On oriented relative clique number
Electronic Notes in Discrete Mathematics, 2015 An oriented graph is a directed graph with no cycle of length one or two. The relative clique number of an oriented graph is the order of a largest subset X of vertices such that each pair of vertices are either adjacent or connected by a directed 2-path. It is known that the oriented relative clique number of a planar graph is at most 80.
Sandip Das, Swathyprabhu Mj, Sagnik Sen
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Forcing clique immersions through chromatic number [PDF]
Electronic Notes in Discrete Mathematics, 2016 Building on recent work of Dvo k and Yepremyan, we show that every simple graph of minimum degree $7t+7$ contains $K_t$ as an immersion and that every graph with chromatic number at least $3.54t + 4$ contains $K_t$ as an immersion. We also show that every graph on $n$ vertices with no stable set of size three contains $K_{2\lfloor n/5 \rfloor}$ as ...
Gauthier G., Le T. -N., Wollan P.
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Distance signless Laplacian eigenvalues, diameter, and clique number [PDF]
Discrete Mathematics Letters, 2022 Saleem Khan, Shariefuddin Pirzada
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Characteristics of Complexity: Clique Number of a Polytope Graph and Rectangle Covering Number
Моделирование и анализ информационных систем, 2014 In the 1980s V.A. Bondarenko found that the clique number of the graph of a polytope in many cases corresponds to the actual complexity of the optimization problem on the vertices of the polytope.
A. N. Maksimenko
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Ramsey numbers of cubes versus cliques [PDF]
Combinatorica, 2014 26 ...
Conlon, David +3 more
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