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Related papers: Aperiodicity Conditions in Topological $k$-Graphs

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This paper is comprised of two related parts. First we discuss which k-graph algebras have faithful gauge invariant traces, where the gauge action of $\T^k$ is the canonical one. We give a sufficient condition for the existence of such a…

Operator Algebras · Mathematics 2007-05-23 David Pask , Adam Rennie , Aidan Sims

The topological containment problem is known to be polynomial-time solvable for any fixed pattern graph $H$, but good characterisations have been found for only a handful of non-trivial pattern graphs. The complete graph on five vertices,…

Discrete Mathematics · Computer Science 2017-05-05 Rebecca Robinson , Graham Farr

Building on previous work by Cameron et al. in [3], we give a recurrence for computing the number of acyclic orientations of complete $k$-partite graphs, which can be implemented to obtain a dynamic programming algorithm running in time…

Combinatorics · Mathematics 2018-08-09 Veselin Blagoev

We propose a definition of graph subshifts of finite type that can be seen as extending both the notions of subshifts of finite type from classical symbolic dynamics and finitely presented groups from combinatorial group theory. These are…

Discrete Mathematics · Computer Science 2026-05-05 Pablo Arrighi , Amélia Durbec , Pierre Guillon

In this paper we study the structure of $k$-transitive closures of directed paths and formulate several properties. Concept of $k$-transitive orientation generalize the traditional concept of transitive orientation of a graph.

Combinatorics · Mathematics 2014-12-24 Krzysztof Pszczoła

We characterise the form of all simple, finite graphs for which the girth of the graph is equal to the circumference of the graph. We apply this to prove a bound on the number of edges in such a graph.

Combinatorics · Mathematics 2022-10-11 Lewis Stanton , Jeffrey Thompson

In this paper, we discuss the Hamiltonicity of graphs in terms of Wiener index, hyper-Wiener index and Harary index of their quasi-complement or complement. Firstly, we give some sufficient conditions for an balanced bipartite graph with…

Combinatorics · Mathematics 2018-04-10 Guidong Yu , Lifang Ren , Gaixiang Cai

In a series of three papers we develop an end space theory for digraphs. Here in the second paper we introduce the topological space $|D|$ formed by a digraph $D$ together with its ends and limit edges. We then characterise those digraphs…

Combinatorics · Mathematics 2020-09-08 Carl Bürger , Ruben Melcher

In 1985, Golumbic and Scheinerman established an equivalence between comparability graphs and containment graphs, graphs whose vertices represent sets, with edges indicating set containment. A few years earlier, McMorris and Zaslavsky…

Combinatorics · Mathematics 2025-03-31 Ketai Chen , Jared DeLeo , Owen Henderschedt

We describe two kinds of regular invariant measures on the boundary path space of a second countable topological graph, which allows us to describe all extremal tracial weights on the graph C$^{*}$-algebra which are not gauge-invariant.…

Operator Algebras · Mathematics 2024-11-20 Johannes Christensen

We introduce a new model of indeterminacy in graphs: instead of specifying all the edges of the graph, the input contains all triples of vertices that form a connected subgraph. In general, different (labelled) graphs may have the same set…

Discrete Mathematics · Computer Science 2023-03-14 Paul Bastide , Linda Cook , Jeff Erickson , Carla Groenland , Marc van Kreveld , Isja Mannens , Jordi L. Vermeulen

We introduce $k$-robust clique complexes, a family of simplicial complexes that generalizes the traditional clique complex. Here, a subset of vertices forms a simplex provided it does not contain an independent set of size $k$. We…

Combinatorics · Mathematics 2026-04-02 Marek Filakovský

Erd\H{o}s proved an upper bound on the number of edges in an $n$-vertex non-Hamiltonian graph with given minimum degree and showed sharpness via two members of a particular graph family. F\"{u}redi, Kostochka and Luo showed that these two…

Combinatorics · Mathematics 2025-04-03 Zhanar Berikkyzy , Kirsten Hogenson , Rachel Kirsch , Jessica McDonald

Random K-out graphs are used in several applications including modeling by sensor networks secured by the random pairwise key predistribution scheme, and payment channel networks. The random K-out graph with $n$ nodes is constructed as…

Information Theory · Computer Science 2022-10-12 Mansi Sood , Osman Yagan

A graph $G$ is $k$-edge geodetic graph if every edge of $G$ lies in at least one geodesic of length $k$. We studied some basic properties of $k$-edge geodetic graphs. We investigated the $k$ edge-geodeticity of complete bipartite graph…

Combinatorics · Mathematics 2024-08-13 Satyam Guragain , Ravi Srivastava

We investigate the K-theory of twisted higher-rank-graph algebras by adapting parts of Elliott's computation of the K-theory of the rotation algebras. We show that each 2-cocycle on a higher-rank graph taking values in an abelian group…

Operator Algebras · Mathematics 2012-11-08 Alex Kumjian , David Pask , Aidan Sims

This paper introduces a novel topology, referred to as the star topology, on finite graphs. By treating vertices and edges as points in a unified space, we explore continuous maps between Bare representations of a graph and their…

Combinatorics · Mathematics 2025-07-21 Rodolfo E. Maza

We prove Menger-type results in which the obtained paths are pairwise non-adjacent, both for graphs of bounded maximum degree and, more generally, for graphs excluding a topological minor. We further show better bounds in the subcubic case,…

Combinatorics · Mathematics 2025-10-29 Kevin Hendrey , Sergey Norin , Raphael Steiner , Jérémie Turcotte

The problem of characterizing maximal non-Hamiltonian graphs may be naturally extended to characterizing graphs that are maximal with respect to non-traceability and beyond that to $t$-path traceability. We show how traceability behaves…

Combinatorics · Mathematics 2017-06-14 Kashif Bari , Michael E. O'Sullivan

We study the question of whether, for a given class of finite graphs, one can define, for each graph of the class, a linear ordering in monadic second-order logic, possibly with the help of monadic parameters. We consider two variants of…

Logic in Computer Science · Computer Science 2015-07-01 Achim Blumensath , Bruno Courcelle