Results 1 to 10 of about 28,180 (165)
On almost distance-regular graphs [PDF]
Journal of Combinatorial Theory - Series A, 2011 Distance-regular graphs are a key concept in Algebraic Combinatorics and have given rise to several generalizations, such as association schemes. Motivated by spectral and other algebraic characterizations of distance-regular graphs, we study `almost distance-regular graphs'.
Cristina Dalfó, E Garriga, M A Fiol
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On the coset graph construction of distance-regular graphs
Discrete Mathematics, 2022 We show that no more new distance-regular graphs in the tables of the book of (Brouwer, Cohen, Neumaier, 1989) can be produced by using the coset graph of additive completely regular codes over finite fields.
Patrick Sole +2 more
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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 the distance spectrum of certain distance biregular graphs
The American Journal of Combinatorics, 2023 In this article we present an infinite family of bipartite distance biregular graphs having an arbitrarily large diameter and whose distance matrices have exactly four distinct eigenvalues. This result answers a question posed by F.
Miriam Abdon +2 more
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Orientable -distance magic regular graphs
AKCE International Journal of Graphs and Combinatorics, 2021 Hefetz, Mütze, and Schwartz conjectured that every connected undirected graph admits an antimagic orientation (Hefetz et al., 2010). In this paper we support the analogous question for distance magic labeling. Let be an Abelian group of order .
Paweł Dyrlaga, Karolina Szopa
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ON A CLASS OF EDGE-TRANSITIVE DISTANCE-REGULAR ANTIPODAL COVERS OF COMPLETE GRAPHS
Ural Mathematical Journal, 2021 The paper is devoted to the problem of classification of edge-transitive distance-regular antipodal covers of complete graphs. This extends the classification of those covers that are arc-transitive, which has been settled except for some tricky cases ...
Ludmila Yu. Tsiovkina
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Transitive distance-regular graphs from linear groups $L(3,q)$, $q = 2,3,4,5$ [PDF]
Transactions on Combinatorics, 2020 In this paper we classify distance-regular graphs, including strongly regular graphs, admitting a transitive action of the linear groups $L(3,2)$, $L(3,3)$, $L(3,4)$ and $L(3,5)$ for which the rank of the permutation representation is at most 15.
Andrea Svob
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Edge-distance-regular graphs [PDF]
Journal of Combinatorial Theory, Series A, 2011 Edge-distance-regularity is a concept recently introduced by the authors which is similar to that of distance-regularity, but now the graph is seen from each of its edges instead of from its vertices. More precisely, a graph Γ with adjacency matrix A is edge-distance-regular when it is distance-regular around each of its edges and with the same ...
Cámara Vallejo, Marc +4 more
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ON DISTANCE–REGULAR GRAPHS OF DIAMETER 3 WITH EIGENVALUE \(\theta=1\)
Ural Mathematical Journal, 2022 For a distance-regular graph \(\Gamma\) of diameter 3, the graph \(\Gamma_i\) can be strongly regular for \(i=2\) or 3. J.Kulen and co-authors found the parameters of a strongly regular graph \(\Gamma_2\) given the intersection array of the graph ...
Alexander A. Makhnev +2 more
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The distance spectrum of two new operations of graphs [PDF]
Transactions on Combinatorics, 2020 Let $G$ be a connected graph with vertex set $V(G)=\{v_1, v_2,\ldots,v_n\}$. The distance matrix $D=D(G)$ of $G$ is defined so that its $(i,j)$-entry is equal to the distance $d_G(v_i,v_j)$ between the vertices $v_i$ and $v_j$ of $G$. The eigenvalues
Zikai Tang +3 more
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