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Related papers: Counting acyclic and strong digraphs by descents

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We prove a strong dichotomy result for countably-infinite oriented graphs; that is, we prove that for all countably-infinite oriented graphs $G$, either (i) there is a countably-infinite tournament $K$ such that $G\not\subseteq K$, or (ii)…

Combinatorics · Mathematics 2024-05-02 Alistair Benford , Louis DeBiasio , Paul Larson

We introduces the umodules, a generalisation of the notion of graph module. The theory we develop captures among others undirected graphs, tournaments, digraphs, and $2-$structures. We show that, under some axioms, a unique decomposition…

Data Structures and Algorithms · Computer Science 2009-09-29 Binh-Minh Bui-Xuan , Michel Habib , Vincent Limouzy , Fabien De Montgolfier

Grammar inference deals with determining (preferable simple) models/grammars consistent with a set of observations. There is a large body of research on grammar inference within the theory of formal languages. However, there is surprisingly…

Machine Learning · Computer Science 2009-02-02 Hendrik Blockeel , Robert Brijder

Functional digraphs are unlabelled finite digraphs where each vertex has exactly one out-neighbor. They are isomorphic classes of finite discrete-time dynamical systems. Endowed with the direct sum and product, functional digraphs form a…

Combinatorics · Mathematics 2026-03-04 Florian Bridoux , Christophe Crespelle , Thi Ha Duong Phan , Adrien Richard

Graphlet counting is an important problem as it has numerous applications in several fields, including social network analysis, biological network analysis, transaction network analysis, etc. Most of the practical networks are dynamic. A…

Data Structures and Algorithms · Computer Science 2023-08-29 Hriday G , Pranav Saikiran Sista , Apurba Das

Subgraph counting aims to count occurrences of a template T in a given network G(V, E). It is a powerful graph analysis tool and has found real-world applications in diverse domains. Scaling subgraph counting problems is known to be memory…

Distributed, Parallel, and Cluster Computing · Computer Science 2020-10-06 Langshi Chen , Jiayu Li , Ariful Azad , Cenk Sahinalp , Madhav Marathe , Anil Vullikanti , Andrey Nikolaev , Egor Smirnov , Ruslan Israfilov , Judy Qiu

The chromatic number of a directed graph is the minimum number of induced acyclic subdigraphs that cover its vertex set, and accordingly, the chromatic number of a tournament is the minimum number of transitive subtournaments that cover its…

Combinatorics · Mathematics 2024-04-09 Felix Klingelhoefer , Alantha Newman

Brushing of graphs is a graph searching process in which the searching agents are called brushes. We focus on brushing directed graphs based on a new model in which the brushes can only travel in the same direction as the orientation of the…

Combinatorics · Mathematics 2024-10-08 Jared Howell , Sulani D. Kavirathne , David A. Pike

Entanglement is a complexity measure of digraphs that origins in fixed-point logics. Its combinatorial purpose is to measure the nested depth of cycles in digraphs. We address the problem of characterizing the structure of graphs of…

Computer Science and Game Theory · Computer Science 2009-04-13 Walid Belkhir

The directions of an infinite graph $G$ are a tangle-like description of its ends: they are choice functions that choose compatibly for all finite vertex sets $X\subseteq V(G)$ a component of $G-X$. Although every direction is induced by a…

Combinatorics · Mathematics 2021-01-19 Jan Kurkofka , Ruben Melcher

For a digraph $D$ of order $n$ and an integer $1 \leq k \leq n-1$, the $k$-token digraph of $D$ is the graph whose vertices are all $k$-subsets of vertices of $D$ and, given two such $k$-subsets $A$ and $B$, $(A,B)$ is an arc in the…

The atom graph of a graph is the graph whose vertices are the atoms obtained by clique minimal separator decomposition of this graph, and whose edges are the edges of all possible atom trees of this graph. We provide two efficient…

Data Structures and Algorithms · Computer Science 2016-07-12 Anne Berry , Geneviève Simonet

We describe a procedure for the generation of functional digraphs up to isomorphism; these are digraphs with uniform outdegree 1, also called mapping patterns, finite endofunctions, or finite discrete-time dynamical systems. This procedure…

Data Structures and Algorithms · Computer Science 2024-09-04 Oscar Defrain , Antonio E. Porreca , Ekaterina Timofeeva

A graph is called (generically) rigid in $\mathbb{R}^d$ if, for any choice of sufficiently generic edge lengths, it can be embedded in $\mathbb{R}^d$ in a finite number of distinct ways, modulo rigid transformations. Here we deal with the…

Computational Geometry · Computer Science 2017-01-26 Ioannis Z. Emiris , Ioannis Psarros

The dichromatic and diachromatic numbers of a digraph are the minimum and maximum numbers of colors, respectively, in acyclic and complete colorings of the digraph. In this paper, we construct, for all $r \leq t$, non-symmetric digraphs…

Combinatorics · Mathematics 2025-08-25 Mika Olsen , Christian Rubio-Montiel , Alejandra Silva Ramirez

This paper has dual aims. First is to develop practical universal coding methods for unlabeled graphs. Second is to use these for graph anomaly detection. The paper develops two coding methods for unlabeled graphs: one based on the degree…

Information Theory · Computer Science 2018-04-10 Anders Host-Madsen , June Zhang

Given a complete graph with positive weights on its edges, we define the weight of a subset of edges as the product of weights of the edges in the subset and consider sums (partition functions) of weights over subsets of various kinds:…

Combinatorics · Mathematics 2013-05-14 Alexander Barvinok

In this article, we study directed graphs (digraphs) with a coloring constraint due to Von Neumann and related to Nim-type games. This is equivalent to the notion of kernels of digraphs, which appears in numerous fields of research such as…

Combinatorics · Mathematics 2012-02-06 Cyril Banderier , Jean-Marie Le Bars , Vlady Ravelomanana

Divisible design digraphs which can be obtained as Cayley digraphs are studied. A characterization of divisible design Cayley digraphs in terms of the generating sets is given. Further, we give several constructions of divisible design…

Combinatorics · Mathematics 2019-10-25 Dean Crnkovic , Hadi Kharaghani , Andrea Svob

We consider complete graphs with edge weights and/or node weights taking values in some set. In the first part of this paper, we show that a large number of graphs are completely determined, up to isomorphism, by the distribution of their…

Combinatorics · Mathematics 2007-10-11 Mireille Boutin , Gregor Kemper