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Related papers: A note on watchman's walks in de Bruijn graphs

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We consider the Distinct Shortest Walks problem. Given two vertices $s$ and $t$ of a graph database $\mathcal{D}$ and a regular path query, enumerate all walks of minimal length from $s$ to $t$ that carry a label that conforms to the query.…

Data Structures and Algorithms · Computer Science 2024-03-08 Claire David , Nadime Francis , Victor Marsault

We investigate the computational complexity of finding temporally disjoint paths or walks in temporal graphs. There, the edge set changes over discrete time steps and a temporal path (resp. walk) uses edges that appear at monotonically…

Data Structures and Algorithms · Computer Science 2021-05-25 Nina Klobas , George B. Mertzios , Hendrik Molter , Rolf Niedermeier , Philipp Zschoche

Let $n \ge 5$ and $k\ge 4$ be positive integers. We determine the maximum size of digraphs of order n that avoid distinct walks of length k with the same endpoints. We also characterize the extremal digraphs attaining this maximum number…

Combinatorics · Mathematics 2016-08-23 Zejun Huang , Zhenhua Lyu , Pu Qiao

We investigate the Drazin invertibility of adjacency matrices associated with a class of oriented graphs known as oriented Dutch windmill graphs. By analyzing walks of prescribed lengths and exploiting the structure of the minimal…

Combinatorics · Mathematics 2026-03-17 C. Mendes Araújo , Faustino Maciala , Pedro Patrício

This paper studies the problem of proper-walk connection number: given an undirected connected graph, our aim is to colour its edges with as few colours as possible so that there exists a properly coloured walk between every pair of…

Discrete Mathematics · Computer Science 2020-09-11 Jørgen Bang-Jensen , Thomas Bellitto , Anders Yeo

A digraph $G$ is \emph{$k$-geodetic} if for any pair of (not necessarily distinct) vertices $u,v \in V(G)$ there is at most one walk of length $\leq k$ from $u$ to $v$ in $G$. In this paper we determine the largest possible size of a…

Combinatorics · Mathematics 2022-03-29 James Tuite , Grahame Erskine , Nika Salia

A queue layout of a graph consists of a linear order on the vertices and an assignment of the edges to queues, such that no two edges in a single queue are nested. The minimum number of queues needed in a queue layout of a graph is called…

Discrete Mathematics · Computer Science 2016-08-23 Veit Wiechert

In this paper, we provide a novel enumeration algorithm for the set of all walks of a given length within a directed graph. Our algorithm has worst-case constant delay between outputting succinct representations of such walks, after a…

Data Structures and Algorithms · Computer Science 2024-01-08 Duncan Adamson , Pawel Gawrychowski , Florin Manea

There are presently two models for quantum walks on graphs. The "coined" walk uses discrete time steps, and contains, besides the particle making the walk, a second quantum system, the coin, that determines the direction in which the…

Quantum Physics · Physics 2009-11-10 Mark Hillery , Janos Bergou , Edgar Feldman

The $k$-th power of the adjacency matrix of a simple undirected graph represents the number of walks with length $k$ between pairs of nodes. As a walk where no node repeats, a path is a walk where each node is only visited once. The set of…

Combinatorics · Mathematics 2022-09-20 Ivan Jokić , Piet Van Mieghem

The 1-2-3 Conjecture, introduced by Karo\'nski, {\L}uczak, and Thomason in 2004, was recently solved by Keusch. This implies that, for any connected graph $G$ different from $K_2$, we can turn $G$ into a locally irregular multigraph $M(G)$,…

Discrete Mathematics · Computer Science 2025-06-27 Julien Bensmail , Romain Bourneuf , Paul Colinot , Samuel Humeau , Timothée Martinod

A (directed) temporal graph is a (directed) graph whose edges are available only at specific times during its (discretized) lifetime $\tau$. In this setting, we ask that walks respect the temporal aspect by defining $\textit{temporal…

Discrete Mathematics · Computer Science 2025-10-15 Allen Ibiapina , Raul Lopes , Andrea Marino , Ana Silva

For positive integers $k,n$, a de Bruijn sequence $B(k,n)$ is a finite sequence of elements drawn from $k$ characters whose subwords of length $n$ are exactly the $k^n$ words of length $n$ on $k$ characters. This paper introduces the…

Combinatorics · Mathematics 2016-08-31 Christie S. Burris , Francis C. Motta , Patrick D. Shipman

The de Bruijn graph, its sequences, and their various generalizations, have found many applications in information theory, including many new ones in the last decade. In this paper, motivated by a coding problem for emerging memory…

Information Theory · Computer Science 2020-05-08 Yeow Meng Chee , Tuvi Etzion , Han Mao Kiah , Alexander Vardy , Van Khu Vu , Eitan yaakobi

A $t$-walk-regular graph is a graph for which the number of walks of given length between two vertices depends only on the distance between these two vertices, as long as this distance is at most $t$. Such graphs generalize distance-regular…

Combinatorics · Mathematics 2015-11-25 Marc Cámara , Edwin R. van Dam , Jack H. Koolen , Jongyook Park

Min orderings give a vertex ordering characterization, common to some graphs and digraphs such as interval graphs, complements of threshold tolerance graphs (known as co-TT graphs), and two-directional orthogonal ray graphs. An adjusted…

Discrete Mathematics · Computer Science 2018-10-16 Asahi Takaoka

In this article, we develop a theory for understanding the traces left by a random walk in the vicinity of a randomly chosen reference vertex. The analysis is related to interlacements but goes beyond previous research by showing weak limit…

Probability · Mathematics 2024-03-25 Steffen Dereich

Given a digraph D, the minimum semi-degree of D is the minimum of its minimum indegree and its minimum outdegree. D is k-ordered Hamiltonian if for every ordered sequence of k distinct vertices there is a directed Hamilton cycle which…

Combinatorics · Mathematics 2007-07-12 Daniela Kühn , Deryk Osthus , Andrew Young

The number of walks from one vertex to another in a finite graph can be counted by the adjacency matrix. In this paper, we prove two theorems that connect the graph Laplacian with two types of walks in a graph. By defining two types of…

Combinatorics · Mathematics 2017-07-13 Chengzheng Yu

The Grover walk is one of the most well-studied quantum walks on graphs. In this paper, we investigate its periodicity to reveal the relationship between the quantum walk and the underlying graph, focusing particularly on the…

Quantum Physics · Physics 2022-12-01 Yusuke Yoshie