Results 31 to 40 of about 42,350 (268)

Shilla distance-regular graphs

European Journal of Combinatorics, 2010
14 ...
Jack H. Koolen, Jongyook Park
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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, Rinovia Simanjuntak   +1 more
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The distance seidel spectrum of some graph operations [PDF]

Journal of Hyperstructures
The 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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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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Distance-regular Subgraphs in a Distance-regular Graph, IV

European Journal of Combinatorics, 1995
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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On distance-regularity in graphs

Journal of Combinatorial Theory, Series B, 1982
AbstractIf A is the adjacency matrix of a graph G, then Ai is the adjacency matrix of the graph on the same vertex set in which a pair of vertices is adjacent if and only if their distance apart is i in G. If G is distance-regular, then Ai is a polynomial of degree i in A. It is shown that the converse is also true.
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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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GRAPHS \(\Gamma\) OF DIAMETER 4 FOR WHICH \(\Gamma_{3,4}\) IS A STRONGLY REGULAR GRAPH WITH \(\mu=4,6\)

Ural Mathematical Journal
We consider antipodal graphs \(\Gamma\) of diameter 4 for which  \(\Gamma_{1,2}\) is a strongly regular graph. A.A. Makhnev and D.V. Paduchikh noticed that, in this case, \(\Delta=\Gamma_{3,4}\) is a strongly regular graph without triangles.
Alexander A. Makhnev, Mikhail P. Golubyatnikov, Konstantin S. Efimov   +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, Maryam Baghipur, Kinkar Ch. Das, Yilun Shang   +3 more
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Distance-Regular Graphs and Halved Graphs

European Journal of Combinatorics, 1986
Let G be a bipartite distance-regular graph with bipartition \(V(G)=X\cup Y\). Let \(V(G')=X\) and, for x and y in X, let x be adjacent to y in G' if and only if x is of distance two from y in G. Then G' is called a halved graph of G, and is distance-regular. This paper discusses whether G' is one of the known, large-diameter, distance-regular graphs.
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