activity
20112026
most citedA bound for the distinguishing index of regular graphs

12 citations · 23 across the 23 of their papers we have counts for

collaborators

39 papers

math.CO2026

Countable Graphs with Finite Path-width: Characterisation and Universality

Tony Huynh, Freddie Illingworth, Nikolai Karol +4

We study path-width and the closely related parameter line-width in countably infinite graphs. Our first result characterises the graphs of finite path-width: they are the graphs t…

math.CO2026

The 2-Cops-Move Cop Number of Graphs on the Torus, Klein Bottle, and Projective Plane

Florian Lehner, Alan Sun

We study the -cops-move variant of the game of cops and robber, in which at most two cops may move in each turn. Let denote the corresponding cop number. We prove that…

math.CO2023

Chromatic number is not tournament-local

António Girão, Kevin Hendrey, Freddie Illingworth +4

Scott and Seymour conjectured the existence of a function such that, for every graph and tournament on the same vertex set, $χ(G) \geqs…

math.CO2023

Asymmetrizing infinite trees

Wilfried Imrich, Rafał Kalinowski, Florian Lehner +2

A graph is asymmetrizable if it has a set of vertices whose setwise stablizer only consists of the identity automorphism. The motion of a graph is the minimum number of ver…

math.GR2022

Asymmetric colouring of locally compact permutation groups

Florian Lehner

Let for a countable set . Call a colouring of asymmetric, if the identity is the only element of which preserves all colours. The motion (also…

math.PR2022

Tipsy cop and tipsy robber: collisions of biased random walks on graphs

Pamela E. Harris, Erik Insko, Florian Lehner

Introduced by Harris, Insko, Prieto Langarica, Stoisavljevic, and Sullivan, the \emph{tipsy cop and drunken robber} is a variant of the cop and robber game on graphs in which the r…