On the oriented diameter of graphs with given minimum degree

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Cochran, Garner, Wang, Zhiyu
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866910910116790272
author Cochran, Garner
Wang, Zhiyu
author_facet Cochran, Garner
Wang, Zhiyu
contents Erdős, Pach, Pollack, and Tuza [\textit{J. Combin. Theory Ser. B, 47(1) (1989), 73-79}] proved that the diameter of a connected $n$-vertex graph with minimum degree $δ$ is at most $\frac{3n}{δ+1}+O(1)$. The oriented diameter of an undirected graph $G$, denoted by $\overrightarrow{\text{diam}}(G)$, is the minimum diameter of a strongly connected orientation of $G$. Bau and Dankelmann [\textit{European J. Combin., 49 (2015), 126-133}] showed that for every bridgeless $n$-vertex graph $G$ with minimum degree $δ$, $\overrightarrow{\text{diam}}(G) \leq \frac{11n}{δ+1}+9$. They also showed an infinite family of graphs with oriented diameter at least $\frac{3n}{δ+1} + O(1)$ and posed the problem of determining the smallest possible value $c$ for which $\overrightarrow{\text{diam}}(G) \leq c \cdot\frac{3n}{δ+1}+O(1)$ holds. In this paper, we show that the smallest value $c$ such that the upper bound above holds for all $δ\geq 2$ is $1$, which is best possible.
format Preprint
id arxiv_https___arxiv_org_abs_2409_06587
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle On the oriented diameter of graphs with given minimum degree
Cochran, Garner
Wang, Zhiyu
Combinatorics
05C12, 05C20, 05C35
Erdős, Pach, Pollack, and Tuza [\textit{J. Combin. Theory Ser. B, 47(1) (1989), 73-79}] proved that the diameter of a connected $n$-vertex graph with minimum degree $δ$ is at most $\frac{3n}{δ+1}+O(1)$. The oriented diameter of an undirected graph $G$, denoted by $\overrightarrow{\text{diam}}(G)$, is the minimum diameter of a strongly connected orientation of $G$. Bau and Dankelmann [\textit{European J. Combin., 49 (2015), 126-133}] showed that for every bridgeless $n$-vertex graph $G$ with minimum degree $δ$, $\overrightarrow{\text{diam}}(G) \leq \frac{11n}{δ+1}+9$. They also showed an infinite family of graphs with oriented diameter at least $\frac{3n}{δ+1} + O(1)$ and posed the problem of determining the smallest possible value $c$ for which $\overrightarrow{\text{diam}}(G) \leq c \cdot\frac{3n}{δ+1}+O(1)$ holds. In this paper, we show that the smallest value $c$ such that the upper bound above holds for all $δ\geq 2$ is $1$, which is best possible.
title On the oriented diameter of graphs with given minimum degree
topic Combinatorics
05C12, 05C20, 05C35
url https://arxiv.org/abs/2409.06587