Please use this identifier to cite or link to this item: http://hdl.handle.net/10995/103154
Title: Distance-regular graph with intersection array {27, 20, 7; 1, 4, 21} does not exist
Authors: Efimov, K. S.
Makhnev, A. A.
Issue Date: 2020
Publisher: Krasovskii Institute of Mathematics and Mechanics
Citation: Efimov K. S. Distance-regular graph with intersection array {27, 20, 7; 1, 4, 21} does not exist / K. S. Efimov, A. A. Makhnev. — DOI 10.15826/UMJ.2020.2.006 // Ural Mathematical Journal. — 2020. — Vol. 6. — Iss. 2. — P. 63-67.
Abstract: 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, 18}, and {27, 20, 7; 1, 4, 21}. Automorphisms of graphs with intersection ar- rays {18, 15, 9; 1, 1, 10} and {24, 21, 3; 1, 3, 18} were found earlier by A.A. Makhnev and D.V. Paduchikh. In this paper, it is proved that a graph with the intersection array {27, 20, 7; 1, 4, 21} does not exist. © 2020, Krasovskii Institute of Mathematics and Mechanics. All rights reserved.
Keywords: AUTOMORPHISM
DISTANCE-REGULAR GRAPH
GRAPH Г WITH STRONGLY REGULAR GRAPH Г3
URI: http://hdl.handle.net/10995/103154
Access: info:eu-repo/semantics/openAccess
SCOPUS ID: 85099576176
PURE ID: 20513126
51895165-7025-4ff6-8d8f-a04dc0f39f3a
ISSN: 24143952
DOI: 10.15826/UMJ.2020.2.006
metadata.dc.description.sponsorship: This work was supported by RFBR and NSFC (project No. 20-51-53013).
Appears in Collections:Научные публикации, проиндексированные в SCOPUS и WoS CC

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