Results 11 to 20 of about 629,769 (266)
Discrete Mathematics, 1980 AbstractWe consider the Ramsey number r(sK2, G) where sK2(s⩾1) denotes a set of s disjoint edges and G is an arbitrary finite simple graph with no isolated vertices. We obtain upper and lower bounds in the general case. Exact results are obtained for certain classes of graphs.
Faudree, R.J., Schelp, R.H., Sheehan, J.
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A Short Proof of the Size of Edge-Extremal Chordal Graphs
Journal of Mathematical Sciences and Modelling, 2022 [3] have recently determined the maximum number of edges of a chordal graph with a maximum degree less than $d$ and the matching number at most $\nu$ by exhibiting a family of chordal graphs achieving this bound. We provide simple proof of their result.
Mordechai Shalom
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Matching Number, Independence Number, and Covering Vertex Number of Γ(Zn)
Mathematics, 2019 Graph invariants are the properties of graphs that do not change under graph isomorphisms, the independent set decision problem, vertex covering problem, and matching number problem are known to be NP-Hard, and hence it is not believed that there are ...
Eman AbuHijleh +3 more
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Matching number and characteristic polynomial of a graph
Journal of Taibah University for Science, 2020 Matching number and the spectral properties depending on the characteristic polynomial of a graph obtained by means of the adjacency polynomial has many interesting applications in different areas of science.
Aysun Yurttas Gunes +3 more
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Counterexamples to a conjecture on matching Kneser graphs [PDF]
Transactions on Combinatorics, 2023 Let $G$ be a graph and $r\in\mathbb{N}$. The matching Kneser graph $\textsf{KG}(G, rK_2)$ is a graph whose vertex set is the set of $r$-matchings in $G$ and two vertices are adjacent if their corresponding matchings are edge-disjoint. In [M. Alishahi and
Moharram N. Iradmusa
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The extremal graphs with respect to their nullity
Journal of Inequalities and Applications, 2016 The nullity of a graph G, denoted by η ( G ) $\eta(G)$ , is the multiplicity of the eigenvalue zero of its adjacency matrix. In this paper, we determine all graphs with η ( G ) = n ( G ) − 2 m ( G ) − c ( G ) $\eta(G)=n(G) - 2m(G) -c(G)$ , where c ( G ) =
Sa Rula, An Chang, Yirong Zheng
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Residual Closeness, Matching Number and Chromatic Number
The Computer Journal, 2022 Abstract Residual closeness is a novel graph-based network vulnerability parameter. In this model, links are perfectly reliable and the nodes fail independently of each other. We characterize those graphs with maximum residual closeness and those connected graphs with minimum residual closeness when matching number (chromatic number ...
Yanna Wang, Bo Zhou
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Bipartite rainbow numbers of matchings
Discrete Mathematics, 2009 8 ...
Li, Xueliang, Tu, Jianhua, Jin, Zemin
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Two Degree Distance Based Topological Indices of Chemical Trees
IEEE Access, 2019 Let G = (VG, EG) be a simple and connected graph. The eccentric connectivity index of G is represented as ξc(G) = Σx∈VG degG(x)ecG(x), where degG(x) and ecG(x) represent the degree and the eccentricity of x, respectively.
Shehnaz Akhter
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Matching preclusion number of graphs [PDF]
Theoretical Computer Science, 2019 23 ...
Zhao Wang +3 more
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