Results 21 to 30 of about 491,070 (354)
There is no (95, 40, 12, 20) strongly regular graph [PDF]
Journal of combinatorial designs (Print), 2016 We show that there is no (95, 40, 12, 20) strongly regular graph and, consequently, there is no (96, 45, 24, 18) strongly regular graph, no nontrivial regular two‐graph on 96 vertices, and no partial geometry pg(4, 9, 2).
Jernej Azarija, Tilen Marc
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On the Clique Number of a Strongly Regular Graph [PDF]
Electronic Journal of Combinatorics, 2016 We determine new upper bounds for the clique numbers of strongly regular graphs in terms of their parameters. These bounds improve on the Delsarte bound for infinitely many feasible parameter tuples for strongly regular graphs, including infinitely many ...
Gary R. W. Greaves, L. H. Soicher
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Regularity of Pythagorean neutrosophic graphs with an illustration in MCDM
AIMS Mathematics, 2022 Pythagorean neutrosophic set is an extension of a neutrosophic set which represents incomplete, uncertain and imprecise details. Pythagorean neutrosophic graphs (PNG) are more flexible than fuzzy, intuitionistic, and neutrosophic models.
D. Ajay +4 more
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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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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.
Haemers, W.H., Touchev, V.D.
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DISTANCE-REGULAR GRAPH WITH INTERSECTION ARRAY {27, 20, 7; 1, 4, 21} DOES NOT EXIST
Ural Mathematical Journal, 2020 In the class of distance-regular graphs of diameter 3 there are 5 intersection arrays of graphs with at most 28 vertices and noninteger eigenvalue. These arrays are \(\{18,14,5;1,2,14\}\), \(\{18,15,9;1,1,10\}\), \(\{21,16,10;1,2,12\}\), \(\{24,21,3;1,3 ...
Konstantin S. Efimov +1 more
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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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There Is No Strongly Regular Graph with Parameters (460, 153, 32, 60) [PDF]
, 2015 We prove that there is no strongly regular graph (SRG) with parameters (460, 153, 32, 60). The proof is based on a recent lower bound on the number of 4-cliques in a SRG and some applications of Euclidean representation of SRGs.
Andriy Bondarenko +4 more
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Characterization of strongly regular integral circulant graphs by spectral approach
Applicable Analysis and Discrete Mathematics, 2022 The integral circulant graph ICGn(D) has the vertex set Zn = {0, 1, 2, . . . , n? 1} and vertices a and b are adjacent if gcd(a ? b, n) ? D, where D ? Dn, Dn = {d : d | n, 1 ? d < n}.
Milan Basic
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MASALAH EIGEN DAN EIGENMODE MATRIKS ATAS ALJABAR MIN-PLUS
Barekeng, 2021 Eigen problems and eigenmode are important components related to square matrices. In max-plus algebra, a square matrix can be represented in the form of a graph called a communication graph.
Eka Widia Rahayu +2 more
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