English
Related papers

Related papers: Decomposing a Graph into Unigraphs

200 papers

Unigraphs are graphs identifiable up to isomorphism from their degree sequences. Given a class $\mathcal{A}$ of graphs, we define the class of $\mathcal{A}$-unigraphs to be graphs identifiable from degree sequence and membership in…

Combinatorics · Mathematics 2024-06-07 R. Whitman

A graph that is completely determined by its degree sequence is called a unigraph. In 2000, Regina Tyshkevich published one of the most important papers on unigraphs. There are two parts to the paper: a decomposition theorem that describes…

Combinatorics · Mathematics 2026-01-06 Christine T. Cheng , Chelsea Ann Lambert

A k-ranking of a graph G is a labeling of the vertices of G with values from {1,...,k} such that any path joining two vertices with the same label contains a vertex having a higher label. The tree-depth of G is the smallest value of k for…

Combinatorics · Mathematics 2015-11-12 Michael D. Barrus , John Sinkovic

In the past decades for more and more graph classes the Graph Isomorphism Problem was shown to be solvable in polynomial time. An interesting family of graph classes arises from intersection graphs of geometric objects. In this work we show…

Data Structures and Algorithms · Computer Science 2016-06-23 Daniel Neuen

A k-ranking of a graph G is a labeling of the vertices of G with values from {1,...,k} such that any path joining two vertices with the same label contains a vertex having a higher label. The tree-depth of G is the smallest value of k for…

Combinatorics · Mathematics 2015-02-19 Michael D. Barrus , John Sinkovic

The graph entropy describes the structural information of graph. Motivated by the definition of graph entropy in general graphs, the graph entropy of hypergraphs based on Laplacian degree are defined. Some results on graph entropy of simple…

Combinatorics · Mathematics 2020-03-30 Pengli Lu , Yulong Xue

A $k$-edge-colored graph is a finite, simple graph with edges labeled by numbers $1,\ldots,k$. A function from the vertex set of one $k$-edge-colored graph to another is a homomorphism if the endpoints of any edge are mapped to two…

Combinatorics · Mathematics 2021-12-17 Grzegorz Guśpiel , Grzegorz Gutowski

A metric basis in a graph $G$ is a smallest possible set $S$ of vertices of $G$, with the property that any two vertices of $G$ are uniquely recognized by using a vector of distances to the vertices in $S$. A strong metric basis is a…

Combinatorics · Mathematics 2025-09-08 Anni Hakanen , Ville Junnila , Tero Laihonen , Ismael G. Yero

We give characterizations of the structure and degree sequences of hereditary unigraphs, those graphs for which every induced subgraph is the unique realization of its degree sequence. The class of hereditary unigraphs properly contains the…

Combinatorics · Mathematics 2015-08-04 Michael D. Barrus

The spectrum of the $k$-power hypergraph of a graph $G$ is called the $k$-ordered spectrum of $G$.If graphs $G_1$ and $G_2$ have same $k$-ordered spectrum for all positive integer $k\geq2$, $G_1$ and $G_2$ are said to be high-ordered…

Combinatorics · Mathematics 2021-11-09 Lixiang Chen , Lizhu Sun , Changjiang Bu

We analyse properties of geometric intersection graphs to show the strict containment between some natural classes of geometric intersection graphs. In particular, we show the following properties: - A graph $G$ is outerplanar if and only…

Combinatorics · Mathematics 2017-02-02 Sergio Cabello , Miha Jejčič

A graph with degree sequence $\pi$ is a \emph{unigraph} if it is isomorphic to every graph that has degree sequence $\pi$. The class of unigraphs is not hereditary and in this paper we study the related hereditary class HCU, the hereditary…

Combinatorics · Mathematics 2023-08-24 Michael D. Barrus , Ann N. Trenk , Rebecca Whitman

A 1-factor of a hypergraph $G=(X,W)$ is a set of hyperedges such that every vertex of $G$ is incident to exactly one hyperedge from the set. A 1-factorization is a partition of all hyperedges of $G$ into disjoint 1-factors. The adjacency…

Combinatorics · Mathematics 2016-12-06 Anna Taranenko

Graphs derived from groups are a widely studied class of graphs, motivated by their highly symmetric structure. In particular, G-graphs offer an easy and interesting alternative construction of semi-symmetric graphs. After recalling the…

Combinatorics · Mathematics 2016-11-25 David Ellison , Ruxandra Marinescu-Ghemeci , Cerasela Tanasescu

In this paper we will apply the tensor and its traces to investigate the spectral characterization of unicyclic graphs. Let $G$ be a graph and $G^m$ be the $m$-th power (hypergraph) of $G$. The spectrum of $G$ is referring to its adjacency…

Combinatorics · Mathematics 2025-07-22 Yi-Zheng Fan , Hong-Xia Yang , Jian Zheng

A (simple) hypergraph is a family H of pairwise incomparable sets of a finite set. We say that a hypergraph H is a domination hypergraph if there is at least a graph G such that the collection of minimal dominating sets of G is equal to H.…

Combinatorics · Mathematics 2016-05-06 Jaume Martí-Farré , Mercè Mora , José Luis Ruiz

The Subgraph Isomorphism problem asks, given a host graph G on n vertices and a pattern graph P on k vertices, whether G contains a subgraph isomorphic to P. The restriction of this problem to planar graphs has often been considered. After…

Discrete Mathematics · Computer Science 2015-03-19 Paul Bonsma

A hypergraph is said to be $1$-Sperner if for every two hyperedges the smallest of their two set differences is of size one. We present several applications of $1$-Sperner hypergraphs and their structure to graphs. In particular, we…

Combinatorics · Mathematics 2018-05-30 Endre Boros , Vladimir Gurvich , Martin Milanič

The $k$-dominating graph $D_k(G)$ of a graph $G$ is defined on the vertex set consisting of dominating sets of $G$ with cardinality at most $k$, two such sets being adjacent if they differ by either adding or deleting a single vertex. A…

Combinatorics · Mathematics 2016-04-26 Saeid Alikhani , Davood Fatehi , Sandi Klavžar

We call a finite undirected graph minimally k-matchable if it has at least k distinct perfect matchings but deleting any edge results in a graph which has not. An odd subdivision of some graph G is any graph obtained by replacing every edge…

Combinatorics · Mathematics 2016-08-05 Gasper Fijavz , Matthias Kriesell
‹ Prev 1 2 3 10 Next ›