On automorphisms of a distance-regular graph with intersection array {99, 84, 30; 1, 6, 54}
-
Konstantin S. Efimov
and
Aleksandr A. Makhnev
Abstract
Recently it was shown that a distance-regular graph in which neighbourhoods of vertices are strongly regular with parameters (99,14,1,2) has intersection array {99,84,1;1,14,99}, {99,84,1;1,12,99} or {99,84,30;1,6,54}. In the present paper we find possible automorphisms of a graph with the intersection array {99,84,30;1,6,54}. It is shown, in particular, that such a graph is not point-symmetric.
Originally published in Diskretnaya Matematika (2017) 29, №1, 10–16 (in Russian).
Funding source: Russian Science Foundation
Award Identifier / Grant number: 14-11-00061
Funding source: Russian Foundation for Basic Research
Award Identifier / Grant number: 14-01-31298
Funding statement: This work was carried out with the financial support of the Russian Science Foundation (grant no. 14-11-00061) (Theorem 1) and under the agreement no. 02.A03.21.0006 between the Ministry of Education and Science of the Russian Federation and the Ural Federal University of 27.08.2013 (Theorem 2). The first-named author was also supported by the Russian Foundation for Basic Research (grant no. 14-01-31298) (Theorem 2).
References
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© 2018 walter de Gruyter GmbH, Berlin/Boston
Articles in the same Issue
- Frontmatter
- Solving systems of linear Boolean equations with noisy right-hand sides over the reals
- Reduced multitype critical branching processes in random environment
- On automorphisms of a distance-regular graph with intersection array {99, 84, 30; 1, 6, 54}
- On the best choice of a branching variable in the subset sum problem
- On periodic properties of polylinear shift registers
- Upper estimate of a combinatorial sum
Articles in the same Issue
- Frontmatter
- Solving systems of linear Boolean equations with noisy right-hand sides over the reals
- Reduced multitype critical branching processes in random environment
- On automorphisms of a distance-regular graph with intersection array {99, 84, 30; 1, 6, 54}
- On the best choice of a branching variable in the subset sum problem
- On periodic properties of polylinear shift registers
- Upper estimate of a combinatorial sum
