activity
20152021
most citedA sufficient condition for Hamiltonicity in locally finite graphs

15 citations · 34 across the 12 of their papers we have counts for

collaborators

16 papers

math.CO2021

Disjoint dijoins for classes of dicuts in finite and infinite digraphs

J. Pascal Gollin, Karl Heuer, Konstantinos Stavropoulos

A dicut in a directed graph is a cut for which all of its edges are directed to a common side of the cut. A famous theorem of Lucchesi and Younger states that in every finite digra…

math.CO2021

Hamilton-laceable bi-powers of locally finite bipartite graphs

Karl Heuer

In this paper we strengthen a result due to Li by showing that the third bi-power of a locally finite connected bipartite graph that admits a perfect matching is Hamilton-laceable,…

math.CO2020

Ubiquity in graphs III: Ubiquity of locally finite graphs with extensive tree-decompositions

Nathan Bowler, Christian Elbracht, Joshua Erde +4

A graph is said to be ubiquitous, if every graph that contains arbitrarily many disjoint -minors automatically contains infinitely many disjoint -minors. The well-kno…

math.CO2020

Even Circuits in Oriented Matroids

Karl Heuer, Raphael Steiner, Sebastian Wiederrecht

In this paper we generalise the even directed cycle problem, which asks whether a given digraph contains a directed cycle of even length, to orientations of regular matroids. We de…

math.CO2020★ 1 cited

Forcing Hamiltonicity in locally finite graphs via forbidden induced subgraphs II: paws

Karl Heuer, Deniz Sarikaya

In this paper we extend a result about a sufficient condition for Hamiltonicity for finite graphs by Broersma and Veldmann to locally finite graphs. In order to do this we use topo…

math.CO2020

Forcing Hamiltonicity in locally finite graphs via forbidden induced subgraphs I: nets and bulls

Karl Heuer, Deniz Sarikaya

In a series of papers, of which this is the first, we study sufficient conditions for Hamiltonicity in terms of forbidden induced subgraphs and extend such results to locally finit…

math.CO2019

On the Infinite Lucchesi-Younger Conjecture I

J. Pascal Gollin, Karl Heuer

A dicut in a directed graph is a cut for which all of its edges are directed to a common side of the cut. A famous theorem of Lucchesi and Younger states that in every finite digra…

math.CO2019★ 12 cited

A sufficient local degree condition for Hamiltonicity in locally finite claw-free graphs

Karl Heuer

Among the well-known sufficient degree conditions for the Hamiltonicity of a finite graph, the condition of Asratian and Khachatrian is the weakest and thus gives the strongest res…

math.CO2019★ 15 cited

A sufficient condition for Hamiltonicity in locally finite graphs

Karl Heuer

Using topological circles in the Freudenthal compactification of a graph as infinite cycles, we extend to locally finite graphs a result of Oberly and Sumner on the Hamiltonicity o…

math.CO2018

Characterising -connected sets in infinite graphs

J. Pascal Gollin, Karl Heuer

A -connected set in an infinite graph, where is an integer, is a set of vertices such that any two of its subsets of the same size can be connected by $\el…

math.CO2018

Ubiquity in graphs II: Ubiquity of graphs with nowhere-linear end structure

Nathan Bowler, Christian Elbracht, Joshua Erde +4

A graph is said to be -ubiquitous, where is the minor relation between graphs, if whenever is a graph with for all , the…

math.CO2018★ 1 cited

Ubiquity in graphs I: Topological ubiquity of trees

Nathan Bowler, Christian Elbracht, Joshua Erde +4

Let be a relation between graphs. We say a graph is \emph{-ubiquitous} if whenever is a graph with for all $n \in \mathb…

math.CO2018

An analogue of Edmonds' Branching Theorem for infinite digraphs

J. Pascal Gollin, Karl Heuer

We extend Edmonds' Branching Theorem to locally finite infinite digraphs. As examples of Oxley or Aharoni and Thomassen show, this cannot be done using ordinary arborescences, whos…

math.CO2017

Infinite end-devouring sets of rays with prescribed start vertices

J. Pascal Gollin, Karl Heuer

We prove that every end of a graph contains either uncountably many disjoint rays or a set of disjoint rays that meet all rays of the end and start at any prescribed feasible set o…

math.CO2017★ 2 cited

Hamiltonicity in locally finite graphs: two extensions and a counterexample

Karl Heuer

We state a sufficient condition for the square of a locally finite graph to contain a Hamilton circle, extending a result of Harary and Schwenk about finite graphs. We also give an…

math.CO2015★ 3 cited

Excluding a full grid minor

Karl Heuer

In this paper we characterise the graphs containing a grid minor in a similar way as it has been done by Halin for graphs with an $\mathbb{N} \times…