Results 41 to 50 of about 542,793 (319)
Some spectral and quasi-spectral characterizations of distance-regular graphs [PDF]
, 2016 © . This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/In this paper we consider the concept of preintersection numbers of a graph.
Abiad, Aida +2 more
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The spectral excess theorem for distance-regular graphs having distance-d graph with fewer distinct eigenvalues [PDF]
, 2015 Let G be a distance-regular graph with diameter d and Kneser graph K=Gd, the distance-d graph of G. We say that G is partially antipodal when K has fewer distinct eigenvalues than G. In particular, this is the case of antipodal distance-regular graphs (K
Fiol Mora, Miquel Àngel
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On distance labelings of 2-regular graphs
Electronic Journal of Graph Theory and Applications, 2021 Let G be a graph with |V(G)| vertices and ψ : V(G) → {1, 2, 3, ... , |V(G)|} be a bijective function. The weight of a vertex v ∈ V(G) under ψ is wψ(v) = ∑u ∈ N(v)ψ(u). The function ψ is called a distance magic labeling of G, if wψ(v) is a constant for
Anak Agung Gede Ngurah +1 more
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On a version of the spectral excess theorem
Electronic Journal of Graph Theory and Applications, 2020 Given a regular (connected) graph G=(X,E) with adjacency matrix A, d+1 distinct eigenvalues, and diameter D, we give a characterization of when its distance matrix AD is a polynomial in A, in terms of the adjacency spectrum of G and the arithmetic (or ...
Miquel Àngel Fiol, Safet Penjic
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The distance seidel spectrum of some graph operations [PDF]
Journal of HyperstructuresThe distance matrix, distance eigenvalue, and distance energy of a connected graph have been studied in detail in literature where as the study on distance seidel matrix associated with a connected graph is in progress. The eigenvalues ∂1S≥∂2S≥ ...
Deena Scaria, Indulal Gopal
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Edge-distance-regular graphs are distance-regular
Journal of Combinatorial Theory, Series A, 2013 A graph is edge-distance-regular when it is distance-regular around each of its edges and it has the same intersection numbers for any edge taken as a root. In this paper we give some (combinatorial and algebraic) proofs of the fact that every edge-distance-regular graph $\G$ is distance-regular and homogeneous.
Cámara Vallejo, Marc +4 more
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Ural Mathematical Journal, 2021 The vertex distance complement (VDC) matrix \(\textit{C}\), of a connected graph \(G\) with vertex set consisting of \(n\) vertices, is a real symmetric matrix \([c_{ij}]\) that takes the value \(n - d_{ij}\) where \(d_{ij}\) is the distance between the
Ann Susa Thomas +2 more
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Sharp Bounds on (Generalized) Distance Energy of Graphs
Mathematics, 2020 Given a simple connected graph G, let D ( G ) be the distance matrix, D L ( G ) be the distance Laplacian matrix, D Q ( G ) be the distance signless Laplacian matrix, and T r ( G ) be the vertex transmission ...
Abdollah Alhevaz +3 more
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Automorphism groups of the constituent graphs of integral distance graphs
AKCE International Journal of Graphs and Combinatorics, 2023 In this paper, we consider the automorphism groups of Cayley graphs which are a basis of a complete Boolean algebra of strongly regular graphs, one of such graph is the integral distance graph [Formula: see text] The automorphism groups of the integral ...
O. Habineza, E. Mwambene
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On Automorphisms of a Distance-Regular Graph with Intersection Array {125,96,1;1,48,125} [PDF]
Учёные записки Казанского университета: Серия Физико-математические науки, 2017 J. Koolen posed the problem of studying distance-regular graphs in which neighborhoods of vertices are strongly regular graphs with the second eigenvalue ≤ t for the given positive integer t.
V.V. Bitkina, A.A. Makhnev
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