English
Related papers

Related papers: Cartesian products of directed graphs with loops

200 papers

We extend the definition of the Cartesian product to graphs with loops and show that the Sabidussi-Vizing unique factorization theorem for connected finite simple graphs still holds in this context for all connected finite graphs with at…

We investigate the uniqueness of factorisation of possibly disconnected finite graphs with respect to the Cartesian, the strong and the direct product. It is proved that if a graph has $n$ connected components, where $n$ is prime, or…

Combinatorics · Mathematics 2011-03-04 Christiaan E. van de Woestijne

Cartesian products of graphs have been studied extensively since the 1960s. They make it possible to decrease the algorithmic complexity of problems by using the factorization of the product. Hypergraphs were introduced as a generalization…

Discrete Mathematics · Computer Science 2009-09-29 Alain Bretto , Yannick Silvestre , Thierry Vallée

In this note, we extend results about unique $n^{\textrm{th}}$ roots and cancellation of finite disconnected graphs with respect to the Cartesian, the strong and the direct product, to the rooted hierarchical products, and to a modified…

Combinatorics · Mathematics 2026-01-13 Wilfried Imrich , Igor Klep , Daniel Smertnig

It is well-known that all finite connected graphs have a unique prime factor decomposition (PFD) with respect to the strong graph product which can be computed in polynomial time. Essential for the PFD computation is the construction of the…

Discrete Mathematics · Computer Science 2015-01-27 Marc Hellmuth , Manuel Noll , Lydia Ostermeier

If each minimal dominating set in a graph is a minimum dominating set, then the graph is called well-dominated. Since the seminal paper on well-dominated graphs appeared in 1988, the structure of well-dominated graphs from several…

Combinatorics · Mathematics 2021-05-21 Douglas F. Rall

We introduce the factorization graph of a finite group and study its connectedness and forbidden structures. We characterize all finite groups with connected factorization graphs and classify those with connected bipartite factorization…

Group Theory · Mathematics 2019-12-02 Mohammad Farrokhi Derakhshandeh Ghouchan , Ali Azimi

Cartesian products of graphs and hypergraphs have been studied since the 1960s. For (un)directed hypergraphs, unique \emph{prime factor decomposition (PFD)} results with respect to the Cartesian product are known. However, there is still a…

Discrete Mathematics · Computer Science 2015-08-31 Marc Hellmuth , Florian Lehner

We show that if a group can be represented as a graph product of finite directly indecomposable groups, then this representation is unique.

Group Theory · Mathematics 2010-08-09 David G. Radcliffe

A graph is well-dominated if all its minimal dominating sets have the same cardinality. In this paper we prove that at least one factor of every connected, well-dominated Cartesian product is a complete graph, which then allows us to give a…

Combinatorics · Mathematics 2023-10-31 Kirsti Kuenzel , Douglas F. Rall

A graph is \emph{well-dominated} if all of its minimal dominating sets have the same cardinality. We prove that at least one of the factors is well-dominated if the Cartesian product of two graphs is well-dominated. In addition, we show…

Combinatorics · Mathematics 2019-09-24 Sarah E. Anderson , Kirsti Kuenzel , Douglas F. Rall

The three standard products (the Cartesian, the direct and the strong product) of undirected graphs have been wellinvestigated, unique prime factor decomposition (PFD) are known and polynomial time algorithms have been established for…

Discrete Mathematics · Computer Science 2014-11-11 Marc Hellmuth , Tilen Marc

Several variants of hypergraph products have been introduced as generalizations of the strong and direct products of graphs. Here we show that only some of them are associative. In addition to the Cartesian product, these are the minimal…

Combinatorics · Mathematics 2015-11-24 Richard H. Hammack , Marc Hellmuth , Lydia Ostermeier , Peter F. Stadler

We extend a factorization due to Krein to arbitrary analytic functions from the upper half-plane to itself. The factorization represents every such function as a product of fractional linear factors times a function which, generally, has…

Complex Variables · Mathematics 2012-05-08 Hari Bercovici , Dan Timotin

We study linkedness of Cartesian product of graphs and prove that the product of an $a$-linked and a $b$-linked graphs is $(a+b-1)$-linked if the graphs are sufficiently large. Further bounds in terms of connectivity are shown. We determine…

Combinatorics · Mathematics 2014-07-29 Gabor Meszaros

We investigate the computational complexity of the graph primality testing problem with respect to the direct product (also known as Kronecker, cardinal or tensor product). In [1] Imrich proves that both primality testing and a unique prime…

Computational Complexity · Computer Science 2025-11-06 Luca Calderoni , Luciano Margara , Moreno Marzolla

In this note we prove that all connected Cayley graphs of every finite group $Q \times H$ are 1-factorizable, where $Q$ is any non-trivial group of 2-power order and $H$ is any group of odd order.

Combinatorics · Mathematics 2007-05-23 Alireza Abdollahi

In this paper, we explore the concept of the ``matrix product of graphs," initially introduced by Prasad, Sudhakara, Sujatha, and M. Vinay. This operation involves the multiplication of adjacency matrices of two graphs with assigned labels,…

Combinatorics · Mathematics 2023-12-15 Farzad Maghsoudi , Babak Miraftab , Sho Suda

This paper is concerned with the linkedness of Cartesian products of complete graphs. A graph with at least $2k$ vertices is {\it $k$-linked} if, for every set of $2k$ distinct vertices organised in arbitrary $k$ pairs of vertices, there…

Combinatorics · Mathematics 2020-12-11 Leif K. Jorgensen , Guillermo Pineda-Villavicencio , Julien Ugon

Recently, Bapat and Kurata [\textit{Linear Algebra Appl.}, 562(2019), 135-153] defined the Cartesian product of two square matrices $A$ and $B$ as $A\oslash B=A\otimes \J+\J\otimes B$, where $\J$ is the all one matrix of appropriate order…

Combinatorics · Mathematics 2019-01-08 Deepak Sarma
‹ Prev 1 2 3 10 Next ›