| Title:
|
Unbalanced unicyclic and bicyclic graphs with extremal spectral radius (English) |
| Author:
|
Belardo, Francesco |
| Author:
|
Brunetti, Maurizio |
| Author:
|
Ciampella, Adriana |
| Language:
|
English |
| Journal:
|
Czechoslovak Mathematical Journal |
| ISSN:
|
0011-4642 (print) |
| ISSN:
|
1572-9141 (online) |
| Volume:
|
71 |
| Issue:
|
2 |
| Year:
|
2021 |
| Pages:
|
417-433 |
| Summary lang:
|
English |
| . |
| Category:
|
math |
| . |
| Summary:
|
A signed graph $\Gamma $ is a graph whose edges are labeled by signs. If $\Gamma $ has $n$ vertices, its spectral radius is the number $\rho (\Gamma ) := \max \{ | \lambda _i(\Gamma ) | \colon 1 \leq i \leq n \}$, where $\lambda _1(\Gamma ) \geq \cdots \geq \lambda _n(\Gamma )$ are the eigenvalues of the signed adjacency matrix $A(\Gamma )$. Here we determine the signed graphs achieving the minimal or the maximal spectral radius in the classes $\frak U_n$ and $\frak B_n$ of unbalanced unicyclic graphs and unbalanced bicyclic graphs, respectively. (English) |
| Keyword:
|
signed graph |
| Keyword:
|
spectral radius |
| Keyword:
|
bicyclic graph |
| MSC:
|
05C22 |
| MSC:
|
05C50 |
| idZBL:
|
07361077 |
| idMR:
|
MR4263178 |
| DOI:
|
10.21136/CMJ.2020.0403-19 |
| . |
| Date available:
|
2021-05-20T13:42:38Z |
| Last updated:
|
2023-07-03 |
| Stable URL:
|
http://hdl.handle.net/10338.dmlcz/148913 |
| . |
| Reference:
|
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