# DMGT

ISSN 1234-3099 (print version)

ISSN 2083-5892 (electronic version)

# IMPACT FACTOR 2018: 0.741

SCImago Journal Rank (SJR) 2018: 0.763

Rejection Rate (2018-2019): c. 84%

# Discussiones Mathematicae Graph Theory

## SPECTRAL INTEGRAL VARIATION OF TREES

Yi Wang and Yi-Zheng Fan

School of Mathematics and Computational Science
Anhui University, Hefei, Anhui 230039, P.R. China
e-mail: fanyz@ahu.edu.cn

## Abstract

In this paper, we determine all trees with the property that adding a particular edge will result in exactly two Laplacian eigenvalues increasing respectively by 1 and the other Laplacian eigenvalues remaining fixed. We also investigate a situation in which the algebraic connectivity is one of the changed eigenvalues.

Keywords: tree, Laplacian eigenvalues, spectral integral variation, algebraic connectivity.

2000 Mathematics Subject Classification: 05C50, 15A18.

## References

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