A note on median eigenvalues of subcubic graphs

التفاصيل البيبلوغرافية
العنوان: A note on median eigenvalues of subcubic graphs
المؤلفون: Wang, Yuzhenni, Zhang, Xiao-Dong
المصدر: Discrete Applied Mathematics, 2023
سنة النشر: 2023
المجموعة: Mathematics
مصطلحات موضوعية: Mathematics - Combinatorics, 05C50
الوصف: Let $G$ be an simple graph of order $n$ whose adjacency eigenvalues are $\lambda_1\ge\dots\ge\lambda_n$. The HL--index of $G$ is defined to be $R(G)= \max\{|\lambda_{h}|, |\lambda_{l}|\}$ with $h=\left\lfloor\frac{n+1}{2}\right\rfloor$ and $ l=\left\lceil\frac{n+1}{2}\right\rceil.$ Mohar conjectured that $R(G)\le 1$ for every planar subcubic graph $G$. In this note, we prove that Mohar's Conjecture holds for every $K_4$-minor-free subcubic graph. Note that a $K_4$-minor-free graph is also called a series--parallel graph. In addition, $R(G)\le 1$ for every subcubic graph $G$ which contains a subgraph $K_{2,3}$.
Comment: 6 pages, 1figure
نوع الوثيقة: Working Paper
URL الوصول: http://arxiv.org/abs/2311.01884
رقم الانضمام: edsarx.2311.01884
قاعدة البيانات: arXiv