Results 11 to 20 of about 4,115 (305)
Extremal graphs for homomorphisms [PDF]
Journal of Graph Theory, 2011 Summary: The study of graph homomorphisms has a long and distinguished history, with applications in many areas of graph theory. There has been recent interest in counting homomorphisms, and in particular on the question of finding upper bounds for the number of homomorphisms from a graph \(G\) into a fixed image graph \(H\).
Jonathan Cutler, A. J. Radcliffe
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A note on the Ramsey numbers for theta graphs versus the wheel of order 5
AKCE International Journal of Graphs and Combinatorics, 2018 The study of exact values and bounds on the Ramsey numbers of graphs forms an important family of problems in the extremal graph theory. For a set of graphs S and a graph F , the Ramsey number R (S , F) is the smallest positive integer r such that for ...
Mohammed M.M. Jaradat +3 more
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Some problems in extremal graph theory and finite geometry
, 2023 Lazebnik, FelixThis thesis is devoted to the study of several problems in extremal graph theory and finite geometry. We study properties such as girth, spectrum, and automorphism group of various families of algebraically defined graphs. We present a new
Taranchuk, Vladislav
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Construction Algorithm of Given Girth Graphs Based on Quantum Evolution [PDF]
Jisuanji gongcheng, 2017 To construct an extremal graph with a given girth is still a challenging problem of graph theory.Especially when the vertex number increasex combination explosion will appear.Thus,this paper proposes an algorithm for constructing graphs with given girth ...
FENG Xiaohua,SUN Yongqi
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On the conjunctive capacity of graphs [PDF]
, 2013 The investigation of the asymptotic behaviour of various graph parameters in powers of a fixed graph G=(V,E) is motivated by problems in information theory and extremal ...
Chlebikova, Janka +5 more
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Ars Mathematica Contemporanea, 2019 Summary: Let \(G\) be a ribbon graph and \(\mu (G)\) be the number of components of the virtual link formed from \(G\) as a cellularly embedded graph via the medial construction. In this paper we first prove that \(\mu (G) \leq f(G) + \gamma (G)\), where \(f(G)\) and \(\gamma (G)\) are the number of boundary components and Euler genus of \(G ...
Jin, Xian'an, Yan, Qi
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Graph Entropy Based on Strong Coloring of Uniform Hypergraphs
Axioms, 2021 The classical graph entropy based on the vertex coloring proposed by Mowshowitz depends on a graph. In fact, a hypergraph, as a generalization of a graph, can express complex and high-order relations such that it is often used to model complex systems ...
Lusheng Fang +3 more
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Solution to the minimum harmonic index of graphs with given minimum degree [PDF]
Transactions on Combinatorics, 2018 The harmonic index of a graph $G$ is defined as $ H(G)=\sum\limits_{uv\in E(G)}\frac{2}{d(u)+d(v)}$, where $d(u)$ denotes the degree of a vertex $u$ in $G$. Let $\mathcal{G}(n,k)$ be the set of simple $n$-vertex graphs with minimum degree at least $k$
Meili Liang, Bo Cheng, Jianxi Liu
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Discrete Applied Mathematics, 2013 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Timothy D. LeSaulnier, Douglas B. West
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On Extremal Graphs With No Long Paths [PDF]
The Electronic Journal of Combinatorics, 1996 Connected graphs with minimum degree $\delta$ and at least $2\delta + 1$ vertices have paths with at least $2\delta + 1$ vertices. We provide a characterization of all such graphs which have no longer paths.
Asad Ali Ali, William Staton
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