English
Related papers

Related papers: Unimodular graphs and Eisenstein sums

200 papers

Let $G$ be a dense graph with good expansion properties and not too close to being bipartite. Let $\boldsymbol d$ be a graphical degree sequence. Under very weak conditions, we find the number of subgraphs of $G$ with degree sequence…

Combinatorics · Mathematics 2025-08-27 Mikhail Isaev , Brendan D. McKay

Finite graphs that have a common chromatic polynomial have the same number of regular $n$-colorings. A natural question is whether there exists a natural bijection between regular $n$-colorings. We address this question using a functorial…

Combinatorics · Mathematics 2015-08-12 Masahiko Yoshinaga

The domination polynomial of a graph $G$ is given by $D(G,x)=\sum_{k=0}^{n} d_k(G)x^k$ where $d_k(G)$ records the number of $k$-element dominating sets in $G$. A conjecture of Alikhani and Peng asserts that these polynomials have unimodal…

Combinatorics · Mathematics 2026-01-22 Mohamed Omar

We propose the spectral degree exponent as a novel graph metric. Although Hofmeister \cite{HofmeisterThesis} has studied the same metric, we generalise Hofmeister's work to weighted graphs. We provide efficient iterative formulas and bounds…

Combinatorics · Mathematics 2025-02-05 Massimo A. Achterberg , Piet Van Mieghem

We introduce and investigate the solvable graph $\Gamma_\mathfrak{S}(L)$ of a finite-dimensional Lie algebra $L$ over a field $F$. The vertices are the elements outside the solvabilizer $\sol(L)$, and two vertices are adjacent whenever they…

Rings and Algebras · Mathematics 2025-11-12 David Towers , Ismael Gutierrez , Luis Fernandez

It is well known that the spectrum and the Smith normal form of a matrix can be computed in polynomial time. Thus, it is interesting to explore how good are these parameters for distinguishing graphs. This is relevant since it is related to…

Combinatorics · Mathematics 2023-09-28 Carlos A. Alfaro , Ralihe R. Villagrán , Octavio Zapata

This article obtains purely metric counterparts of cornerstone results in the theory of embedding graphs into normed spaces. Our first main result is a metric analogue of Matou\v{s}ek's extrapolation relating the Poincar\'e constants…

Metric Geometry · Mathematics 2026-01-27 Dylan J. Altschuler , Pandelis Dodos , Konstantin Tikhomirov , Konstantinos Tyros

We develop a calculus based on graph enumeration for $S_n$-equivariant motivic invariants of graphically stratified moduli spaces. We apply our theory to the Deligne--Mumford moduli space $\overline{\mathcal{M}}_{g, n}$ and to the space of…

Algebraic Geometry · Mathematics 2025-10-09 Siddarth Kannan , Terry Dekun Song

In this paper, a function on any pair of graphs is defined whose properties are similar to the properties of dot product in vector space. This function enables us to define graph orthogonality and, also, a new metric on isomorphism classes…

Combinatorics · Mathematics 2018-10-23 Ameneh Farhadian

A Nordhaus-Gaddum-type result is a (tight) lower or upper bound on the sum or product of a parameter of a graph and its complement. In this paper some variations are considered. First, recall their theorem, which gives bounds on the sum and…

Combinatorics · Mathematics 2014-09-23 Sunny Joseph Kalayathankal , Susanth C

In this paper, we investigate the Sombor index of the total graph and unit graph of $\mathbb{Z}_n$ which is denoted by $T_{\Gamma}(\mathbb{Z}_n)$ and $G(\mathbb{Z}_n)$ respectively for $n \in \{2k, p^{\alpha}, pq, p^2q\}$ where $p$ and $q$…

Combinatorics · Mathematics 2024-05-14 Abhishek Vaibhav Pathak , Anukul Sachan , Raisa DSouza

We prove that if a unimodular random graph is almost surely planar and has finite expected degree, then it has a combinatorial embedding into the plane which is also unimodular. This implies the claim in the title immediately by a theorem…

Probability · Mathematics 2025-02-14 Adam Timar

We give new characterizations for the class of uniformly dense matroids and study applications of these characterizations to graphic and real representable matroids. We show that a matroid is uniformly dense if and only if its base polytope…

Combinatorics · Mathematics 2026-02-03 Karel Devriendt , Raffaella Mulas

This paper investigates the relations between modular graph forms, which are generalizations of the modular graph functions that were introduced in earlier papers motivated by the structure of the low energy expansion of genus-one Type II…

High Energy Physics - Theory · Physics 2018-07-03 Eric D'Hoker , Michael B. Green

By designating vertices with variables, a simple undirected graph can be augmented to have an associated representing rational function in two variables taking the complex bi-upper halfplane to itself. We give relations between representing…

Complex Variables · Mathematics 2025-11-05 Lily Adlin , Giovani Thai , Samuel Tiscareno , Ryan Tully-Doyle

Let R be a commutative ring with unity, M be an unitary R-module and {\Gamma} be a simple graph. This research article is an interplay of combinatorial and algebraic properties of M . We show a combinatorial object completely determines an…

Commutative Algebra · Mathematics 2017-11-06 Rameez Raja

The Erd\H{o}s, Gr\"unwald, and Weiszfeld theorem is a characterization of those infinite graphs which are Eulerian. That is, infinite graphs that admit infinite Eulerian paths. In this article we prove an effective version of the Erd\H{o}s,…

Combinatorics · Mathematics 2025-03-19 Nicanor Carrasco-Vargas

We relate one-loop scattering amplitudes of massless open- and closed-string states at the level of their low-energy expansion. The modular graph functions resulting from integration over closed-string punctures are observed to follow from…

High Energy Physics - Theory · Physics 2019-03-05 Johannes Broedel , Oliver Schlotterer , Federico Zerbini

We present a formal version of the numbers of vertices, edges, and faces for infinite planar regular triangular meshes of degree r>6. These numbers are defined via Euler summation of sequences obtained from iterated expansions of a convex…

Combinatorics · Mathematics 2025-12-17 Piotr Jędrzejewicz , Mikołaj Marciniak

Let $\Gamma$ be a finite graph and let $\Gamma^{\mathrm{e}}$ be its extension graph. We inductively define a sequence $\{\Gamma_i\}$ of finite induced subgraphs of $\Gamma^{\mathrm{e}}$ through successive applications of an operation called…

Group Theory · Mathematics 2017-08-08 Sang-hyun Kim , Thomas Koberda , Juyoung Lee