H. Holst

activity

20242026

collaborators

3 papers

math.CO2026

On the Spectra of Chromatic Number and Chromatic Index of Cyclic Covers

Guantao Chen, Hein van der Holst, Rong Luo +1

For a fixed integer $ℓ \geq 2$ , we study what values of chromatic index and chromatic number can be attained by some $ℓ$ -fold cyclic cover of a loopless multigraph. For edge-c…

math.CO2025

Strong binding numbers and factors

Guantao Chen, Mikhail Lavrov, Yuying Ma +2

Let $G$ be a simple graph. The $k$ -th neighborhood of a vertex subset $S \subseteq V (G)$ , denoted $I^^{k} (S)$ , is the set of vertices that are adjacent to at least $k$ vertices in $S…

math.CO2024

The stable maximum nullity of digraphs and $1$ -DAGs

Marina Arav, Hein van der Holst

Given a digraph $D = (V, A)$ with vertex-set $V = {1, \dots, n}$ and arc-set $A$ , we denote by $Q (D)$ the set of all real $n \times n$ matrices $B = [b_{u, w}]$ with $b_{u, u} \neq = 0$ for al…

On the Spectra of Chromatic Number and Chromatic Index of Cyclic Covers

Strong binding numbers and factors

The stable maximum nullity of digraphs and 1-DAGs

The stable maximum nullity of digraphs and $1$ -DAGs