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Related papers: Gonality of Expander Graphs

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We show that the expected gonality of a random graph is asymptotic to the number of vertices.

Combinatorics · Mathematics 2016-08-03 Andrew Deveau , David Jensen , Jenna Kainic , Dan Mitropolsky

We prove new lower and upper bounds on the higher gonalities of finite graphs. These bounds are generalizations of known upper and lower bounds for first gonality to higher gonalities, including upper bounds on gonality involving…

The gonality of a graph measures how difficult it is to move chips around the entirety of a graph according to certain chip-firing rules without introducing debt. In this paper we study the gonality of circulant graphs, a class of…

We define a new graph invariant called the scramble number. We show that the scramble number of a graph is a lower bound for the gonality and an upper bound for the treewidth. Unlike the treewidth, the scramble number is not minor monotone,…

Combinatorics · Mathematics 2021-11-08 Michael Harp , Elijah Jackson , David Jensen , Noah Speeter

We find new upper bounds on the size of a minimum totally dominating set for random regular graphs and for regular graphs with large girth. These bounds are obtained through the analysis of a local algorithm using a method due to Hoppen and…

Combinatorics · Mathematics 2020-01-07 Carlos Hoppen , Giovane Mansan

We study tropically planar graphs, which are the graphs that appear in smooth tropical plane curves. We develop necessary conditions for graphs to be tropically planar, and compute the number of tropically planar graphs up to genus $7$. We…

Algebraic Geometry · Mathematics 2020-02-06 Desmond Coles , Neelav Dutta , Sifan Jiang , Ralph Morrison , Andrew Scharf

The scramble number of a graph provides a lower bound for gonality and an upper bound for treewidth, making it a graph invariant of interest. In this paper we study graphs of scramble number at most two, and give a classification of all…

Combinatorics · Mathematics 2022-12-21 Robin Eagleton , Ralph Morrison

Two dimensional rook graphs are the Cartesian product of two complete graphs. In this paper we prove that the gonality of these graphs is the expected value of $(n-1)m$ where $n$ is the size of the smaller complete graph and $m$ is the size…

Combinatorics · Mathematics 2022-05-24 Noah Speeter

It is well known that 3--regular graphs with arbitrarily large girth exist. Three constructions are given that use the former to produce non-Hamiltonian 3--regular graphs without reducing the girth, thereby proving that such graphs with…

Combinatorics · Mathematics 2019-02-28 Michael Haythorpe

The divisorial gonality of a graph is the minimum degree of a positive rank divisor on that graph. We introduce the multiplicity-free gonality of a graph, which restricts our consideration to divisors that place at most \(1\) chip on each…

Combinatorics · Mathematics 2021-07-28 Frances Dean , Max Everett , Ralph Morrison

Estimating numerically the spectral radius of a random walk on a nonamenable graph is complicated, since the cardinality of balls grows exponentially fast with the radius. We propose an algorithm to get a bound from below for this spectral…

Probability · Mathematics 2015-09-30 Sebastien Gouezel

In this article, we discuss when one can extend an r-regular graph to an r + 1 regular by adding edges. Different conditions on the num- ber of vertices n and regularity r are developed. We derive an upper bound of r, depending on n, for…

Combinatorics · Mathematics 2015-09-21 Anirban Banerjee , Saptarshi Bej

A $d$-regular graph on $n$ nodes has at most $T_{\max} = \frac{n}{3} \tbinom{d}{2}$ triangles. We compute the leading asymptotics of the probability that a large random $d$-regular graph has at least $c \cdot T_{\max}$ triangles, and…

Combinatorics · Mathematics 2021-04-16 Pim van der Hoorn , Gabor Lippner , Elchanan Mossel

We examine connections between the gonality, treewidth, and orientable genus of a graph. Especially, we find that hyperelliptic graphs in the sense of Baker and Norine are planar. We give a notion of a bielliptic graph and show that each of…

Number Theory · Mathematics 2017-04-21 James Stankewicz

To any graph we associate a sequence of integers called the gonality sequence of the graph, consisting of the minimum degrees of divisors of increasing rank on the graph. This is a tropical analogue of the gonality sequence of an algebraic…

Combinatorics · Mathematics 2021-04-19 Ivan Aidun , Frances Dean , Ralph Morrison , Teresa Yu , Julie Yuan

Benjamini and Schramm introduced the notion of distributional limit of a sequence of graphs with uniformly bounded valence and studied such limits in the case that the involved graphs are planar. We investigate distributional limits of…

Metric Geometry · Mathematics 2013-09-05 Hossein Namazi , Pekka Pankka , Juan Souto

This survey concerns regular graphs that are extremal with respect to the number of independent sets, and more generally, graph homomorphisms. More precisely, in the family of of $d$-regular graphs, which graph $G$ maximizes/minimizes the…

Combinatorics · Mathematics 2017-11-03 Yufei Zhao

We introduce a model for a growing random graph based on simultaneous reproduction of the vertices. The model can be thought of as a generalisation of the reproducing graphs of Southwell and Cannings and Bonato et al to allow for a random…

Probability · Mathematics 2011-04-20 Jonathan Jordan

We prove that random triangulations of high genus contain very large expander subgraphs, answering a question of Benjamini. Our approach relies on new general criteria for arbitrary graphs to contain large expander subgraphs.

Combinatorics · Mathematics 2026-02-18 Tanguy Lions , Baptiste Louf

We give sufficient conditions under which a random graph with a specified degree sequence is symmetric or asymmetric. In the case of bounded degree sequences, our characterisation captures the phase transition of the symmetry of the random…

Combinatorics · Mathematics 2020-04-07 Lochlan Brick , Pu Gao , Angus Southwell
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