Results 11 to 20 of about 8,008 (169)
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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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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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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On matching number, decomposition and representation of well-formed graph
Electronic Journal of Graph Theory and Applications, 2023 In this paper, we find a special type of non-traceable cubic bridge graph called well-formed graph whose central fragment is isomorphic to a hairy cycle and whose branches are pairwise isomorphic.
Alex Ralph Baisa Nieva, Karen P. Nocum
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The matching number and Hamiltonicity of graphs
AKCE International Journal of Graphs and Combinatorics, 2020 The matching number of a graph G is the size of a maximum matching in the graph. In this note, we present a sufficient condition involving the matching number for the Hamiltonicity of graphs.
Rao Li
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The Regularity of Edge Rings and Matching Numbers
Mathematics, 2020 Let K [ G ] denote the edge ring of a finite connected simple graph G on [ d ] and mat ( G ) the matching number of G. It is shown that reg ( K [ G ] ) ≤ mat ( G ) if G is non-bipartite and K [ G ] is normal,
Jürgen Herzog, Takayuki Hibi
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Binding Number, Toughness and General Matching Extendability in Graphs [PDF]
Discrete Mathematics & Theoretical Computer Science, 2019 A connected graph $G$ with at least $2m + 2n + 2$ vertices which contains a perfect matching is $E(m, n)$-{\it extendable}, if for any two sets of disjoint independent edges $M$ and $N$ with $|M| = m$ and $|N|= n$, there is a perfect matching $F$ in $G ...
Hongliang Lu, Qinglin Yu
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图的补距离矩阵谱半径的最大值(On maximal spectral radius of complementary distance matrix of graphs)
Zhejiang Daxue xuebao. Lixue ban, 2013 We determine the graphs with maximal spectral radius of the complementary distance matrix among simple connected graphs with fixed order and matching number and diameter less than or equal to 2.
SULi(苏莉), LIHong-hai(李红海)
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当匹配数很小时具有最小拉普拉斯谱半径的树(Trees with small matching number and minimum Laplacian spectral radius)
Zhejiang Daxue xuebao. Lixue ban, 2013 考虑了具有最小拉普拉斯谱半径的树的问题.并确定了当匹配数很小时具有最小拉普拉斯谱半径的树.
LINXi-qin(林西芹) +2 more
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Journal of Mathematics, 2022 The matching roots of a simple connected graph G are the roots of the matching polynomial which is defined as MGx=∑k=0n/2−1kmG,kxn−2k, where mG,k is the number of the k matchings of G. Let λ1G denote the largest matching root of the graph G.
Luozhong Gong, Weijun Liu
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