The Lemmens-Seidel conjecture and forbidden subgraphs

Meng Yue Cao; Jack H. Koolen; Yen Chi Roger Lin; Wei Hsuan Yu

doi:10.1016/j.jcta.2021.105538

The Lemmens-Seidel conjecture and forbidden subgraphs

Meng Yue Cao, Jack H. Koolen^*, Yen Chi Roger Lin, Wei Hsuan Yu

^*Corresponding author for this work

Department of Mathematics

Research output: Contribution to journal › Article › peer-review

2 Citations (Scopus)

Abstract

In this paper we show that the conjecture of Lemmens and Seidel of 1973 for systems of equiangular lines with common angle arccos⁡(1/5) is true. Our main tool is forbidden subgraphs for smallest Seidel eigenvalue −5.

Original language	English
Article number	105538
Journal	Journal of Combinatorial Theory. Series A
Volume	185
DOIs	https://doi.org/10.1016/j.jcta.2021.105538
Publication status	Published - 2022 Jan

Keywords

Equiangular lines
Forbidden subgraphs
Pillar method
Seidel matrices

ASJC Scopus subject areas

Theoretical Computer Science
Discrete Mathematics and Combinatorics
Computational Theory and Mathematics

Access to Document

10.1016/j.jcta.2021.105538

Cite this

@article{b0e866032af44bf286952ab3784d15d4,

title = "The Lemmens-Seidel conjecture and forbidden subgraphs",

abstract = "In this paper we show that the conjecture of Lemmens and Seidel of 1973 for systems of equiangular lines with common angle arccos⁡(1/5) is true. Our main tool is forbidden subgraphs for smallest Seidel eigenvalue −5.",

keywords = "Equiangular lines, Forbidden subgraphs, Pillar method, Seidel matrices",

author = "Cao, {Meng Yue} and Koolen, {Jack H.} and Lin, {Yen Chi Roger} and Yu, {Wei Hsuan}",

note = "Publisher Copyright: {\textcopyright} 2021 Elsevier Inc.",

year = "2022",

month = jan,

doi = "10.1016/j.jcta.2021.105538",

language = "English",

volume = "185",

journal = "Journal of Combinatorial Theory. Series A",

issn = "0097-3165",

publisher = "Academic Press Inc.",

}

TY - JOUR

T1 - The Lemmens-Seidel conjecture and forbidden subgraphs

AU - Cao, Meng Yue

AU - Koolen, Jack H.

AU - Lin, Yen Chi Roger

AU - Yu, Wei Hsuan

PY - 2022/1

Y1 - 2022/1

N2 - In this paper we show that the conjecture of Lemmens and Seidel of 1973 for systems of equiangular lines with common angle arccos⁡(1/5) is true. Our main tool is forbidden subgraphs for smallest Seidel eigenvalue −5.

AB - In this paper we show that the conjecture of Lemmens and Seidel of 1973 for systems of equiangular lines with common angle arccos⁡(1/5) is true. Our main tool is forbidden subgraphs for smallest Seidel eigenvalue −5.

KW - Equiangular lines

KW - Forbidden subgraphs

KW - Pillar method

KW - Seidel matrices

UR - http://www.scopus.com/inward/record.url?scp=85114926419&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85114926419&partnerID=8YFLogxK

U2 - 10.1016/j.jcta.2021.105538

DO - 10.1016/j.jcta.2021.105538

M3 - Article

AN - SCOPUS:85114926419

SN - 0097-3165

VL - 185

JO - Journal of Combinatorial Theory. Series A

JF - Journal of Combinatorial Theory. Series A

M1 - 105538

ER -

The Lemmens-Seidel conjecture and forbidden subgraphs

Abstract

Keywords

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Cite this