Results 31 to 40 of about 262 (120)
Extermal properties of Zagreb coindices and degree distance of graphs
, 2010 The degree distance, Zagreb coindices and reverse degree distance of a connected graph have been studied in mathematical chemistry. In this paper some new extremal values of these topological invariants over some special classes of graphs are determined.
S. Hossein-Zadeh, A. Hamzeh, A. Ashrafi
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Special Matrices, 2017 We take as given a real symmetric matrix A, whose graph is a tree T, and the eigenvalues of A, with their multiplicities. Each edge of T may then be classified in one of four categories, based upon the change in multiplicity of a particular eigenvalue ...
Toyonaga Kenji, Johnson Charles R.
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Discussiones Mathematicae Graph Theory, 2022 A branch at a vertex x in a tree is a maximal subtree containing x as an endvertex. The branch-weight of x is the maximum number of edges in any branch at x.
Shang Jen-Ling
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Some improved bounds on two energy-like invariants of some derived graphs
Open Mathematics, 2019 Given a simple graph G, its Laplacian-energy-like invariant LEL(G) and incidence energy IE(G) are the sum of square root of its all Laplacian eigenvalues and signless Laplacian eigenvalues, respectively. This paper obtains some improved bounds on LEL and
Cui Shu-Yu, Tian Gui-Xian
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The Product Connectivity Banhatti Index of A Graph
Discussiones Mathematicae Graph Theory, 2019 Let G = (V, E) be a connected graph with vertex set V (G) and edge set E(G). The product connectivity Banhatti index of a graph G is defined as, PB(G)=∑ue1dG(u)dG(e)$PB(G) = \sum\nolimits_{ue} {{1 \over {\sqrt {{d_G}(u){d_G}(e)} }}}$ where ue means that ...
Kulli V.R. +2 more
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Linear and metric maps on trees via Markov graphs
Commentationes Mathematicae Universitatis Carolinae, 2018 The main focus of combinatorial dynamics is put on the structure of periodic points (and the corresponding orbits) of topological dynamical systems.
Kozerenko Sergiy
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Trees with Unique Least Central Subtrees
Discussiones Mathematicae Graph Theory, 2018 A subtree S of a tree T is a central subtree of T if S has the minimum eccentricity in the join-semilattice of all subtrees of T. Among all subtrees lying in the join-semilattice center, the subtree with minimal size is called the least central subtree ...
Kang Liying, Shan Erfang
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A combinatorial expression for the group inverse of symmetric M-matrices
Special Matrices, 2021 By using combinatorial techniques, we obtain an extension of the matrix-tree theorem for general symmetric M-matrices with no restrictions, this means that we do not have to assume the diagonally dominance hypothesis.
Carmona A., Encinas A.M., Mitjana M.
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New bounds for Randic and GA indices
, 2013 The main goal of this paper is to present some new lower and upper bounds for the Randic and GA indices in terms of Zagreb and modified Zagreb indices.MSC: 05C05, 05C20, 05C90.
V. Lokesha +4 more
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New Directions for Neo-logicism
Bulletin of Symbolic Logic, 2019 prepared by Lukas Daniel Klausner. E-mail: mail@l17r.eu URL: http://repositum.tuwien.ac.at/urn:nbn:at:at-ubtuw:1-116736 Ari Meir Brodsky, A Theory of Stationary Trees and the Balanced Baumgartner–Hajnal– Todorcevic Theorem for Trees, University of ...
Aaron Thomas-Bolduc
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