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In this paper, we present a constructive and proof-relevant development of graph theory, including the notion of maps, their faces, and maps of graphs embedded in the sphere, in homotopy type theory. This allows us to provide an elementary…

Logic in Computer Science · Computer Science 2024-11-20 Jonathan Prieto-Cubides , Håkon Robbestad Gylterud

We examine the structure of Farey maps, which are a class of maps (graph embeddings on surfaces) that have received significant attention recently. We describe how they are related to each other through regular coverings and parallel…

Combinatorics · Mathematics 2021-11-19 Margaret Stanier

We establish a strong, geometric lower bound on the (sequential) topological complexity of the unordered configuration spaces of a general graph. As an application, we show that, for most graphs, the topological complexity eventually…

Algebraic Topology · Mathematics 2026-02-05 Ben Knudsen

Motivated by the successful application of geometry to proving the Harary-Hill Conjecture for "pseudolinear" drawings of $K_n$, we introduce "pseudospherical" drawings of graphs. A spherical drawing of a graph $G$ is a drawing in the unit…

Combinatorics · Mathematics 2021-04-20 Alan Arroyo , R. Bruce Richter , Matthew Sunohara

We prove a coarse version of Halin's Grid Theorem: Every one-ended, locally finite graph that contains the disjoint union of infinitely many rays as an asymptotic minor also contains the half-grid as an asymptotic minor. More generally, we…

Combinatorics · Mathematics 2026-05-27 Sandra Albrechtsen , Matthias Hamann

Pointed pseudo-triangulations are planar minimally rigid graphs embedded in the plane with pointed vertices (adjacent to an angle larger than 180 degrees. In this paper we prove that the opposite statement is also true, namely that planar…

Recently geometric hypergraphs that can be defined by intersections of pseudohalfplanes with a finite point set were defined in a purely combinatorial way. This led to extensions of earlier results about points and halfplanes to…

Combinatorics · Mathematics 2024-02-14 Balázs Keszegh

We study pseudorandomness and pseudorandom generators from the perspective of logical definability. Building on results from ordinary derandomization and finite model theory, we show that it is possible to deterministically construct, in…

Logic in Computer Science · Computer Science 2023-04-25 Jan Dreier , Jamie Tucker-Foltz

End-spaces of infinite graphs naturally generalise the Freudenthal boundary and sit at the interface between graph theory, geometric group theory and topology. Our main result is that every end-space can topologically be represented by a…

Combinatorics · Mathematics 2024-09-02 Jan Kurkofka , Max Pitz

In an early work from 1896, Maschke established the complete list of all finite planar Cayley graphs. This result initiated a long line of research over the next century, aiming at characterizing in a similar way all planar infinite Cayley…

Combinatorics · Mathematics 2025-08-01 Ugo Giocanti

Let $v(F)$ denote the number of vertices in a fixed connected pattern graph $F$. We show an infinite family of patterns $F$ such that the existence of a subgraph isomorphic to $F$ is expressible by a first-order sentence of quantifier depth…

Computational Complexity · Computer Science 2018-02-08 Oleg Verbitsky , Maksim Zhukovskii

Suppose that $F$ is a finite field and $R=M_n(F)$ is the ring of $n$-square matrices over $F$. Here we characterize when the Cayley graph of the additive group of $R$ with respect to the set of invertible elements of $R$, called the unitary…

Combinatorics · Mathematics 2024-04-11 Shahin Rahimi , Ashkan Nikseresht

In this study we consider the problem of triangulated graphs. Precisely we give a necessary and sufficient condition for a graph to be triangulated. This give an alternative characterization of triangulated graphs. Our method is based on…

Combinatorics · Mathematics 2018-11-21 R. Gargouri , H. Najar

This paper is intended as an introductory survey of a newly emerging field: a topological approach to the study of locally finite graphs that crucially incorporates their ends. Topological arcs and circles, which may pass through ends,…

Combinatorics · Mathematics 2012-07-11 Reinhard Diestel

The theory of graph limits represents large graphs by analytic objects called graphons. Graph limits determined by finitely many graph densities, which are represented by finitely forcible graphons, arise in various scenarios, particularly…

Combinatorics · Mathematics 2018-10-10 Jacob W. Cooper , Daniel Kral , Taisa L. Martins

We consider sets and maps defined over an o-minimal structure over the reals, such as real semi-algebraic or subanalytic sets. A {\em monotone map} is a multi-dimensional generalization of a usual univariate monotone function, while the…

Logic · Mathematics 2013-08-19 Saugata Basu , Andrei Gabrielov , Nicolai Vorobjov

We present a novel construction of finite groupoids whose Cayley graphs have large girth even w.r.t. a discounted distance measure that contracts arbitrarily long sequences of edges from the same colour class (sub-groupoid), and only counts…

Combinatorics · Mathematics 2024-01-17 Martin Otto

A novel class of graphs, here named quasiperiodic, are constructed via application of the Horizontal Visibility algorithm to the time series generated along the quasiperiodic route to chaos. We show how the hierarchy of mode-locked regions…

Chaotic Dynamics · Physics 2015-06-04 Bartolo Luque , Fernando J. Ballesteros , Ángel M. Núñez , Alberto Robledo

The Paley graph is a well-known self-complementary pseudo-random graph, defined over a finite field of odd order. We describe an attempt at an analogous construction using fields of even order. Some properties of the graph are noted, such…

Combinatorics · Mathematics 2015-09-18 Andrew Thomason

We consider classes of arbitrary (finite or infinite) graphs of bounded shrub-depth, specifically the classes $\mathrm{TM}_r(d)$ of arbitrary graphs that have tree models of height $d$ and $r$ labels. We show that the graphs of…

Combinatorics · Mathematics 2022-02-15 Abhisekh Sankaran