A note on optimistic strongly regular graphs

doi:10.3969/j.issn.0253-2778.2017.03.001

Journal of University of Science and Technology of China ›› 2017, Vol. 47 ›› Issue (3): 197-203.DOI: 10.3969/j.issn.0253-2778.2017.03.001

• Original Paper • Next Articles

A note on optimistic strongly regular graphs

QIAO Zhi, PAN Yongliang

School of Mathematical Sciences, University of Science and Technology of China, Hefei 230026, China

Received:2015-11-17 Revised:2016-04-10 Accepted:2016-04-10 Online:2023-03-27 Published:2016-04-10
Contact: PAN Yongliang
About author:QIAO Zhi, male, born in 1990, PhD. Research field: Graph theory. E-mail：gesec@mail.ustc.edu.cn
Supported by:
Supported by the Fundamental Research Funds for the Central Universities, the National Natural Science Foundation of China (61272008, 11271348, 10871189).

Abstract

Abstract: It is known that for a fixed integer α≥2, all but finitely many coconnected ones, the strongly regular graphs with smallest eigenvalue -α fall into two infinite families. Graham and Lovász raised the question of whether optimistic graphs exist and it was answered positively by Azarija. Here strongly regular graphs were classified with smallest eigenvalue -3, and the optimistic ones among them were determined.

Key words: coconnected graph, strongly regular graphs, eigenvalue, optimistic graphs

CLC Number:

O157.5

QIAO Zhi, PAN Yongliang. A note on optimistic strongly regular graphs[J]. Journal of University of Science and Technology of China, 2017, 47(3): 197-203.

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A note on optimistic strongly regular graphs

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