Results 21 to 30 of about 286,497 (273)
Approximately strongly regular graphs
Discrete Mathematics, 2023 We give variants of the Krein bound and the absolute bound for graphs with a spectrum similar to that of a strongly regular graph. In particular, we investigate what we call approximately strongly regular graphs. We apply our results to extremal problems. Among other things, we show the following: (1) Caps in $\mathrm{PG}(n, q)$ for which the number of
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Strongly Regular Graphs Having Strongly Regular Subconstituents
Journal of Algebra, 1978 No abstract.
Cameron, P.J. +2 more
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Certain Concepts in Vague Graph with an Application
Discrete Dynamics in Nature and Society, 2022 Vague graphs (VGs), belonging to the FGs family, have good capabilities when faced with problems that cannot be expressed by FGs. When an element’s membership is not clear, neutrality is a good option that can be well-supported by a VG.
Xiaolong Shi +3 more
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Graph isomorphism and Gaussian boson sampling
Special Matrices, 2021 We introduce a connection between a near-term quantum computing device, specifically a Gaussian boson sampler, and the graph isomorphism problem. We propose a scheme where graphs are encoded into quantum states of light, whose properties are then probed ...
Brádler Kamil +4 more
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Transitive $t$-designs and strongly regular graphs constructed from linear groups $L(2,q)$, $q leq 23$ [PDF]
International Journal of Group Theory, 2019 In this paper we construct transitive $t$-designs from the linear groups $L(2,q), q leq 23$. Thereby we classify $t$-designs, $t ge 2$, admitting a transitive action of the linear groups $L(2,q), q leq 23$, up to 35 points and obtained ...
Dean Crnković, Andrea Švob
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Observations on the Lovász θ-Function, Graph Capacity, Eigenvalues, and Strong Products
Entropy, 2023 This paper provides new observations on the Lovász θ-function of graphs. These include a simple closed-form expression of that function for all strongly regular graphs, together with upper and lower bounds on that function for all regular graphs.
Igal Sason
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A unique and novel graph matrix for efficient extraction of structural information of networks
Electronic Journal of Graph Theory and Applications, 2021 In this article, we propose a new type of square matrix associated with an undirected graph by trading off the natural embedded symmetry in them. The proposed matrix is defined using the neighbourhood sets of the vertices, called as neighbourhood matrix
Sivakumar Karunakaran +1 more
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Vulnerability Parameters in Neutrosophic Graphs [PDF]
Neutrosophic Sets and Systems, 2022 Let 𝐺 = (U, V) be a Single valued Neutrosophic graph. A subset 𝑆 ∈ 𝑈(𝐺) is a said to be score equitable set if the score value of any two nodes in S differ by at most one. That is, |𝑠(𝑢)– 𝑠(𝑣)| ≤ 1, 𝑢, 𝑣 ∊ 𝑆. If e is an edge with end vertices u and v and
R.V. Jaikumar +4 more
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Strongly regular graphs with strongly regular decomposition
Linear Algebra and its Applications, 1989 Partitions of strongly regular graphs into two strongly regular subgraphs are studied. Such partitions give rise to quasi-symmetric designs and other types of interesting configurations. Necessary conditions for the existence of such partitions are derived. Several constructions are given and a table of all feasible parameter sets up to 300 vertices is
Haemers, W. H., Higman, Donald G.
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Maximal Product of Graphs under Vague Environment
Mathematical and Computational Applications, 2020 Graph models are found everywhere in natural and human made structures, including process dynamics in physical, biological and social systems. The product of graphs are appropriately used in several combinatorial applications and in the formation of ...
Behnaz Sheikh Hoseini +4 more
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