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Graph-based semantic representations are valuable in natural language processing, where it is often simple and effective to represent linguistic concepts as nodes, and relations as edges between them. Several attempts has been made to find…

Formal Languages and Automata Theory · Computer Science 2021-05-10 Johanna Björklund , Frank Drewes , Anna Jonsson

A word-graph Gw is a digraph represented by a word w such that the vertex-set V(Gw) is the alphabet of w and the edge-set E(Gw) is determined by non-identical adjacent letter pairs in w. In this paper we study the strong-connectivity of…

Combinatorics · Mathematics 2011-08-31 Edward J. L. Bell , Damon Berridge , Paul Rayson

A graph $G = (V, E)$ is said to be word-representable if a word $w$ can be formed using the letters of the alphabet $V$ such that for every pair of vertices $x$ and $y$, $xy \in E$ if and only if $x$ and $y$ alternate in $w$. Gaetz and Ji…

Combinatorics · Mathematics 2025-12-25 Eshwar Srinivasan , Ramesh Hariharasubramanian

The notion of $12$-representable graphs was introduced as a variant of a well-known class of word-representable graphs. Recently, these graphs were shown to be equivalent to the complements of simple-triangle graphs. This indicates that a…

Discrete Mathematics · Computer Science 2023-04-18 Asahi Takaoka

A graph $G = (V, E)$ is said to be word-representable if a word $w$ can be formed using the letters of the alphabet $V$ such that for every pair of vertices $x$ and $y$, $xy \in E$ if and only if $x$ and $y$ alternate in $w$. A…

Combinatorics · Mathematics 2026-01-29 Eshwar Srinivasan , Ramesh Hariharasubramanian

The binomial notation (w u) represents the number of occurrences of the word u as a (scattered) subword in w. We first introduce and study possible uses of a geometrical interpretation of (w ab) and (w ba) when a and b are distinct letters.…

Discrete Mathematics · Computer Science 2025-10-09 Gwenaël Richomme

A graph $G=(V,E)$ is word-representable if there exists a word $w$ over the alphabet $V$ such that letters $x$ and $y$ alternate in $w$ if and only if $xy$ is an edge in $E$. It is known that any word-representable graph $G$ is…

Combinatorics · Mathematics 2016-09-05 Marc Glen , Sergey Kitaev , Artem Pyatkin

The representation of graphs is commonly based on the adjacency matrix concept. This formulation is the foundation of most algebraic and computational approaches to graph processing. The advent of deep learning language models offers a wide…

Artificial Intelligence · Computer Science 2025-12-16 Ezequiel Lopez-Rubio

We introduce a new notation for representing labeled regular bipartite graphs of arbitrary degree. Several enumeration problems for labeled and unlabeled regular bipartite graphs have been introduced. A general algorithm for enumerating all…

Discrete Mathematics · Computer Science 2015-12-31 Vivek S. Nittoor

Series-parallel (SP) graphs are binary edge-labeled graphs with a designated source and target vertex, built using serial and parallel composition. A set of graphs is recognizable if membership depends only on its image under a homomorphism…

Formal Languages and Automata Theory · Computer Science 2026-04-28 Marius Bozga , Radu Iosif , Florian Zuleger

An open question in the theory of word-representable graphs for the past decade has been whether the line graph of a non-word-representable graph is always non-word-representable. By formulating an appropriate optimization problem for the…

Combinatorics · Mathematics 2021-08-06 M M Akbar , P D Akrobotu , C P Brewer

Inflection graphs are highly complex networks representing relationships between inflectional forms of words in human languages. For so-called synthetic languages, such as Latin or Polish, they have particularly interesting structure due to…

Cellular Automata and Lattice Gases · Physics 2023-12-18 Henryk Fukś , Babak Farzad , Yi Cao

Inspired by distributed algorithms, we introduce a new class of finite graph automata that recognize precisely the graph languages definable in monadic second-order logic. For the cases of words and trees, it has been long known that the…

Formal Languages and Automata Theory · Computer Science 2014-04-28 Fabian Reiter

The representation number of a graph is the minimum number of copies of each vertex required to represent the graph as a word, such that the letters corresponding to vertices $x$ and $y$ alternate if and only if $xy$ is an edge in the…

Combinatorics · Mathematics 2025-07-23 Nawaf Shafi Alshammari , Sergey Kitaev , Artem Pyatkin

Representing words by vectors, or embeddings, enables computational reasoning and is foundational to automating natural language tasks. For example, if word embeddings of similar words contain similar values, word similarity can be readily…

Computation and Language · Computer Science 2022-02-02 Carl Allen

It has become a de-facto standard to represent words as elements of a vector space (word2vec, GloVe). While this approach is convenient, it is unnatural for language: words form a graph with a latent hierarchical structure, and this…

Computation and Language · Computer Science 2020-10-07 Max Ryabinin , Sergei Popov , Liudmila Prokhorenkova , Elena Voita

A graph $G = (V,E)$ is word-representable if there is a word $w$ over the alphabet $V$ such that $x$ and $y$ alternate in $w$ if and only if the edge $(x, y)$ is in $G$. It is known [6] that all $3$-colourable graphs are word-representable,…

Combinatorics · Mathematics 2018-10-01 Marc Elliot Glen

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

Learning to fuse vision and language information and representing them is an important research problem with many applications. Recent progresses have leveraged the ideas of pre-training (from language modeling) and attention layers in…

Computer Vision and Pattern Recognition · Computer Science 2020-10-08 Bowen Zhang , Hexiang Hu , Vihan Jain , Eugene Ie , Fei Sha

A double-arborescence is a treelike comparability graph with an all-adjacent vertex. In this paper, we first give a forbidden induced subgraph characterization of double-arborescences, where we prove that double-arborescences are precisely…

Combinatorics · Mathematics 2024-12-24 Tithi Dwary , K. V. Krishna