A Strongly Regular Graph With Parameters (1666, 105, 0, 7) Does not Exist
DOI:
https://doi.org/10.17072/1993-0550-2026-1-29-34Keywords:
graph, regular graph, strongly regular graph, distance-regular graph, intersection numbersAbstract
Note that a non-bipartite triangle-free strongly regular graph with μ = 7 has parameters k = 49s2 + 49s + 7, where s ∈ {1, 2, 7}. In this paper, it is proved that a bipartite distance-regular graph with intersection array {105, 104, 98, 7, 1; 1, 7, 98, 104, 105} does not exist. Consequently, a strongly regular graph with parameters (1666, 105, 0, 7) does not exist.References
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Copyright (c) 2026 Вероника Игоревна Белоусова, Александр Алексеевич Махнев, Альбина Аниуаровна Токбаева
This work is licensed under a Creative Commons Attribution 4.0 International License.
Articles are published under license Creative Commons Attribution 4.0 International (CC BY 4.0).
