Results 11 to 20 of about 1,782 (193)
The Maximal Total Irregularity of Bicyclic Graphs [PDF]
Journal of Applied Mathematics, 2014 In 2012, Abdo and Dimitrov defined the total irregularity of a graph G=(V,E) as irrtG=1/2∑u,v∈VdGu-dGv, where dGu denotes the vertex degree of a vertex u∈V.
Lihua You +3 more
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On the harmonic index of bicyclic graphs
Communications in Combinatorics and Optimization, 2018 The harmonic index of a graph $G$, denoted by $H(G)$, is defined as the sum of weights $2/[d(u)+d(v)]$ over all edges $uv$ of $G$, where $d(u)$ denotes the degree of a vertex $u$. Hu and Zhou [Y. Hu and X. Zhou, WSEAS Trans. Math.
R. Rasi
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Regularity of bicyclic graphs and their powers [PDF]
Journal of Algebra and Its Applications, 2019 Let [Formula: see text] be the edge ideal of a bicyclic graph [Formula: see text] with a dumbbell as the base graph. In this paper, we characterize the Castelnuovo–Mumford regularity of [Formula: see text] in terms of the induced matching number of [Formula: see text]. For the base case of this family of graphs, i.e.
Cid-Ruiz, Yairon +3 more
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The nullity of bicyclic signed graphs [PDF]
Linear and Multilinear Algebra, 2013 Let Γbe a signed graph and let A(Γ) be the adjacency matrix of Γ. The nullity of Γis the multiplicity of eigenvalue zero in the spectrum of A(Γ). In this paper we characterize the signed graphs of order n with nullity n-2 or n-3, and introduce a graph transformation which preserves the nullity.
Fan, Yi-Zheng +2 more
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On the index of unbalanced signed bicyclic graphs [PDF]
Computational and Applied Mathematics, 2021 In this paper, we focus on the index ( largest eigenvalue) of the adjacency matrix of connected signed graphs. We give some general results on the index when the corresponding signed graph is perturbed. As applications, we determine the first five largest index among all unbalanced bicyclic graphs on n >= 36 vertices together with the corresponding ...
Changxiang He +3 more
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The Orderings of Bicyclic Graphs and Connected Graphs by Algebraic Connectivity [PDF]
The Electronic Journal of Combinatorics, 2010 The algebraic connectivity of a graph $G$ is the second smallest eigenvalue of its Laplacian matrix. Let $\mathscr{B}_n$ be the set of all bicyclic graphs of order $n$. In this paper, we determine the last four bicyclic graphs (according to their smallest algebraic connectivities) among all graphs in $\mathscr{B}_n$ when $n\geq 13$.
Jianxi Li, Ji-Ming Guo, Wai Chee Shiu
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Discrete Mathematics, 2008 Let \(\lambda_2\) be the second largest eigenvalue of the adjacency matrix of a graph. Graphs having \(\lambda_2\leq 2\) are called reflexive graphs. Since this property is hereditary, these graphs may be represented through sets of maximal graphs. In this paper, authors continue their previous line of study and construct maximal bicyclic reflexive ...
Zoran Radosavljevic +2 more
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Applied Mathematics Letters, 2005 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Stefan Grünewald, Dragan Stevanovic
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The first Dirichlet eigenvalue of bicyclic graphs [PDF]
Czechoslovak Mathematical Journal, 2012 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Zhang, Guang-Jun, Zhang, Xiao-Dong
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On Omega Index and Average Degree of Graphs
Journal of Mathematics, 2021 Average degree of a graph is defined to be a graph invariant equal to the arithmetic mean of all vertex degrees and has many applications, especially in determining the irregularity degrees of networks and social sciences.
Sadik Delen +3 more
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