Results 1 to 10 of about 117 (114)
On strongly regular graphs with m2 = qm3 and m3 = qm2 for q = 7/2, 7/3, 7/4, 7/5, 7/6 [PDF]
Yugoslav Journal of Operations Research, 2021 We say that a regular graph G of order n and degree r ≥ 1 (which is not the complete graph) is strongly regular if there exist non-negative integers τ and θ such that |Si ∩ Sj| = τ for any two adjacent vertices i and j, and |Si ∩ Sj| = θ for any
Lepović Mirko
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Spreads in Strongly Regular Graphs [PDF]
Designs, Codes and Cryptography, 1996 A spread in any geometry is a set of pairwise disjoint lines that cover all the points. For a partial geometry the point graph (collinearity graph) is strongly regular. Delsarte showed that a clique in a strongly regular graph has at most \(K = 1 - k/s\) vertices, where \(k\) and \(s\) are the largest and smallest eigenvalues of the graph respectively.
Willem H. Haemers, Vladimir D. Tonchev
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The application domain of difference type matrix D(r,0,s,0,t) on some sequence spaces [PDF]
Yugoslav Journal of Operations Research, 2021 We say that a regular graph G of order n and degree r ≥ 1 (which is not the complete graph) is strongly regular if there exist non-negative integers τ and θ such that |Si ∩ Sj | = τ for any two adjacent vertices i and j, and |Si ∩ Sj | = θ for any two ...
Paul Avinoy, Tripathy Binod Chandra
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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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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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On r-Edge Regular Neutrosophic Graphs [PDF]
Neutrosophic Sets and Systems, 2023 We approach learning characteristic on a neutrosophic graph such as r-edge regular neutrosophic graph, strongly edge regular neutrosophic graph and absolute degree of vertex since a neutrosophic set 𝑁𝑆 = {〈𝑥, 𝑁𝑆𝔗(𝑥), 𝑁𝑆𝔩 (𝑥), 𝑁𝑆𝔉(𝑥)〉; 𝑥 ∈ 𝑋} of a ...
M. Kaviyarasu
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An upper bound for difference of energies of a graph and its complement
Examples and Counterexamples, 2023 The A-energy of a graph G, denoted by EA(G), is defined as sum of the absolute values of eigenvalues of adjacency matrix of G. Nikiforov in Nikiforov (2016) proved that EA(G¯)−EA(G)≤2μ¯1and EA(G)−EA(G¯)≤2μ1for any graph G and posed a problem to find best
Harishchandra S. Ramane +2 more
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On the Integrability of Strongly Regular Graphs [PDF]
Graphs and Combinatorics, 2019 Koolen et al. showed that if a connected graph with smallest eigenvalue at least $-3$ has large minimal valency, then it is $2$-integrable. In this paper, we will prove that a lower bound for the minimal valency is 166.
Jack H. Koolen +2 more
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Extension of Strongly Regular Graphs [PDF]
The Electronic Journal of Combinatorics, 2008 The Friendship Theorem states that if any two people in a party have exactly one common friend, then there exists a politician who is a friend of everybody. In this paper, we generalize the Friendship Theorem. Let $\lambda$ be any nonnegative integer and $\mu$ be any positive integer.
Gera, Ralucca, Shen, J.
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Some Chemistry Indices of Clique-Inserted Graph of a Strongly Regular Graph
Complexity, 2021 In this paper, we give the relation between the spectrum of strongly regular graph and its clique-inserted graph. The Laplacian spectrum and the signless Laplacian spectrum of clique-inserted graph of strongly regular graph are calculated.
Chun-Li Kan +3 more
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