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In the past couple of years a rich connection has been found between the fields of descriptive set theory and distributed computing. Frequently, and less surprisingly, finitary algorithms can be adopted to the infinite setting, resulting in…

Logic · Mathematics 2025-02-24 Jan Grebík , Zoltán Vidnyánszky

A 2-edge-coloured graph $G$ is called {\bf locally complete} if for each vertex $v$, the vertices adjacent to $v$ through edges of the same colour induce a complete subgraph in $G$. Locally complete 2-edge-coloured graphs have nice…

Combinatorics · Mathematics 2024-10-08 Jørgen Bang-Jensen , Jing Huang

For a directed acyclic graph, there are two known criteria to decide whether any specific conditional independence statement is implied for all distributions factorized according to the given graph. Both criteria are based on special types…

Statistics Theory · Mathematics 2009-04-03 Giovanni M. Marchetti , Nanny Wermuth

In this paper, some results concerning the colorings of graph powers are presented. The notion of helical graphs is introduced. We show that such graphs are hom-universal with respect to high odd-girth graphs whose $(2t+1)$st power is…

Combinatorics · Mathematics 2008-03-31 Hossein Hajiabolhassan

It is known that the canonical double cover of any connected nonbipartite graph have an automorphism group of the form $H \rtimes \mathbb{Z}_2$, where $H$ is the set of automorphism which preserve bipartite parts. We construct connected…

Combinatorics · Mathematics 2024-06-11 Bartłomiej Bychawski

We study a metric on the set of finite graphs in which two graphs are considered to be similar if they have similar bounded dimensional "factors". We show that limits of convergent graph sequences in this metric can be represented by…

Combinatorics · Mathematics 2016-12-07 Dávid Kunszenti-Kovács , László Lovász , Balázs Szegedy

We prove analogs of Brooks' Theorem for the list-distinguishing chromatic number of different classes of simple finite connected graphs. Moreover, we determine two upper bounds for the list-distinguishing chromatic number of a graph G in…

Combinatorics · Mathematics 2025-07-23 Amitayu Banerjee , Zalán Molnár , Alexa Gopaulsingh

In this paper we will prove that there exists a covariant functor from the category of schemes to the category of graphs. This functor provides a combination between algebraic varieties and combinatorial graphs so that the invariants…

Algebraic Geometry · Mathematics 2009-07-06 Feng-Wen An

The family of cycle completable graphs has several cryptomorphic descriptions, the equivalence of which has heretofore been proven by a laborious implication-cycle that detours through a motivating matrix completion problem. We give a…

Combinatorics · Mathematics 2023-09-06 Maria Chudnovsky , Ian Malcolm Johnson McInnis

In this paper we give a new characterization of the h-vector of the chromatic polynomial of a graph. We introduce reduced chromatic cohomology of a graph and show that h_i are its Betti numbers. We then discuss various combinatorial…

Combinatorics · Mathematics 2007-05-23 Michael Chmutov , Elena Udovina

In this work, we continue the tradition initiated by Geschke, 2011 of viewing the uncountable Borel chromatic number of analytic graphs as cardinal invariants of the continuum. We show that various uncountable Borel chromatic numbers of…

Logic · Mathematics 2022-08-16 Michel Gaspar , Stefan Geschke

We introduce (weak) oddomorphisms of graphs which are homomorphisms with additional constraints based on parity. These maps turn out to have interesting properties (e.g., they preserve planarity), particularly in relation to homomorphism…

Combinatorics · Mathematics 2022-06-22 David E. Roberson

We characterize the completely determined Borel subsets of HYP as exactly the omega_1^{ck} subsets of HYP. As a result, HYP believes there is a Borel well-ordering of the reals, that the Borel Dual Ramsey Theorem fails, and that every Borel…

Logic · Mathematics 2022-03-03 Henry Towsner , Rose Weisshaar , Linda Westrick

We give a cohomological criterion for certain decomposition of Borel graphs, which is an analog of Dunwoody's work on accessibility of groups. As an application, we prove that a Borel graph $(X,G)$ with uniformly bounded degrees of…

Group Theory · Mathematics 2026-03-12 Hiroki Ishikura

In this report, we describe a novel graph invariant for computational graphs (colored directed acylic graphs) and how we used it to generate all distinct computational graphs up to isomorphism for small graphs. The algorithm iteratively…

Discrete Mathematics · Computer Science 2019-02-19 Chris Ying

As an extension of the Brooks theorem, Catlin in 1979 showed that if $H$ is neither an odd cycle nor a complete graph with maximum degree $\Delta(H)$, then $H$ has a vertex $\Delta(H)$-coloring such that one of the color classes is a…

Combinatorics · Mathematics 2020-02-13 Yaser Rowshan , Ali Taherkhani

We study the problem of bi-chromatic coloring of hypergraphs in the LOCAL distributed model of computation. This problem can easily be solved by a randomized local algorithm with no communication. However, it is not known how to solve it…

Data Structures and Algorithms · Computer Science 2019-08-01 Dariusz R. Kowalski , Piotr Krysta

The human brain cortical layer has a convoluted morphology that is unique to each individual. Characterization of the cortical morphology is necessary in longitudinal studies of structural brain change, as well as in discriminating…

Neurons and Cognition · Quantitative Biology 2019-02-21 Sevil Maghsadhagh , Anders Eklund , Hamid Behjat

In this paper we introduce the notion of $\Sigma$-colouring of a graph $G$: For given subsets $\Sigma(v)$ of neighbours of $v$, for every $v\in V(G)$, this is a proper colouring of the vertices of $G$ such that, in addition, vertices that…

Combinatorics · Mathematics 2015-09-28 Omid Amini , Louis Esperet , Jan van den Heuvel

Bipartite graphs are a fundamental concept in graph theory with diverse applications. A graph is bipartite iff it contains no odd cycles, a characteristic that has many implications in diverse fields ranging from matching problems to the…

Combinatorics · Mathematics 2024-12-10 Marzieh Eidi , Sayan Mukherjee