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Related papers: On the spectra of k-uniform threshold hypergraphs

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In this paper extremal problems for uniform hypergraphs are studied in the general setting of hereditary properties. It turns out that extremal problems about edges are particular cases of a general analyic problem about a recently…

Combinatorics · Mathematics 2013-05-14 Vladimir Nikiforov

Here, we represent a general hypergraph by a matrix and study its spectrum. We extend the definition of equitable partition and joining operation for hypergraphs, and use those to compute eigenvalues of different hypergraphs. We derive the…

Combinatorics · Mathematics 2020-01-01 Amitesh Sarkar , Anirban Banerjee

In this paper, we analyse spectral properties of Seidel matrix (denoted by $S$) of connected threshold graphs. We compute the characteristic polynomial and determinant of Seidel matrix of threshold graphs. We derive formulas for the…

Combinatorics · Mathematics 2021-01-12 Santanu Mandal , Ranjit Mehatari

We give some new bounds for the clique and independence numbers of a graph in terms of its eigenvalues.

Combinatorics · Mathematics 2017-01-31 Vladimir Nikiforov

Hypergraphs are a generalization of graphs in which edges can connect any number of vertices. They allow the modeling of complex networks with higher-order interactions, and their spectral theory studies the qualitative properties that can…

Combinatorics · Mathematics 2021-12-01 Raffaella Mulas

We generalize the concept of token graphs to obtain supertoken graphs. In the latter case, there can be more than one token in a vertex. We formally define supertoken graphs and establish their basic properties. Moreover, we provide some…

Combinatorics · Mathematics 2026-04-08 Mónica A. Reyes , Cristina Dalfó , Miquel Àngel Fiol

In this monography, it is proposed to consider the concepts of spectra of edge cuts and edge cycles of a graph as a basic mathematical structure for solving the problem of graph isomorphism. An edge cut is defined by an edge and the…

Combinatorics · Mathematics 2024-06-13 Sergey Kurapov , Maxim Davidovsky

An $r$-uniform hypergraph $H$ consists of a set of vertices $V$ and a set of edges whose elements are $r$-subsets of $V$. We define a hypertree to be a connected hypergraph which contains no cycles. A hypertree spans a hypergraph $H$ if it…

Combinatorics · Mathematics 2020-10-12 Haya S. Aldosari , Catherine Greenhill

In the broad range of studies related to quantum graphs, quantum graph spectra appear as a topic of special interest. They are important in the context of diffusion type problems posed on metric graphs. Theoretical findings suggest that…

Numerical Analysis · Mathematics 2023-12-15 Chong-Son Dröge , Anna Weller

We view hyper-graphs as incidence graphs, i.e. bipartite graphs with a set of nodes representing vertices and a set of nodes representing hyper-edges, with two nodes being adjacent if the corresponding vertex belongs to the corresponding…

Logic in Computer Science · Computer Science 2015-05-08 Nans Lefebvre

Quantum graphs have attracted attention from mathematicians for some time. A quantum graph is defined by having a Laplacian on each edge of a metric graph and imposing boundary conditions at the vertices to get an eigenvalue problem. A…

Spectral Theory · Mathematics 2022-07-26 Mats-Erik Pistol , Pavel Kurasov

A 1-planar graph refers to a graph that can be drawn on the plane such that each edge has at most one crossing. In this paper, focusing on the spectral Tur\'{a}n-type problems of $1$-planar graphs, we determine completely the unique…

Combinatorics · Mathematics 2025-12-16 Weilun Xu , An Chang

We characterize the graphs with loops whose degree sequences have no repeated values and find their adjacency spectrum. In the case of simple graphs, such graphs are called anti-regular graphs and are examples of threshold graphs. The…

Combinatorics · Mathematics 2019-12-16 Cesar O. Aguilar

The spectral theory of graphs provides a bridge between classical signal processing and the nascent field of graph signal processing. In this paper, a spectral graph analogy to Heisenberg's celebrated uncertainty principle is developed.…

Information Theory · Computer Science 2013-08-02 Ameya Agaskar , Yue M. Lu

The spectral radius of a graph is the spectral radius of its adjacency matrix. A threshold graph is a simple graph whose vertices can be ordered as $v_1, v_2, \ldots, v_n$, so that for each $2 \le i \le n$, vertex $v_i$ is either adjacent…

Combinatorics · Mathematics 2024-12-23 Péter Csikvári , Ivan Damnjanović , Dragan Stevanović , Stephan Wagner

We examine the capacity of the complementarity spectrum to distinguish non-isomorphic digraphs. We focus on the seven families with exactly three complementarity eigenvalues. Our findings reveal that in some, but not all families, any two…

Combinatorics · Mathematics 2024-03-19 Diego Bravo , Florencia Cubría , Marcelo Fiori , Gustavo Rama

Various properties of a hypergraph can be explored through its spectrum. In this paper,we estimate the bound for the sum of $t,\,t\in[1,n]$, largest eigenvalues of a $k$-uniform hypergraph of order $n$. Also, we characterize the $k$-uniform…

Combinatorics · Mathematics 2025-07-10 Liya Jess Kurian , Chithra A.

In this paper we study the complementarity spectrum of digraphs, with special attention to the problem of digraph characterization through this complementarity spectrum. That is, whether two non-isomorphic digraphs with the same number of…

Combinatorics · Mathematics 2021-10-11 Diego Bravo , Florencia Cubría , Marcelo Fiori , Vilmar Trevisan

In recent work on equiangular lines, Jiang, Tidor, Yuan, Zhang, and Zhao showed that a connected bounded degree graph has sublinear second eigenvalue multiplicity. More generally they show that there cannot be too many eigenvalues near the…

Probability · Mathematics 2024-01-17 Mikolaj Fraczyk , Ben Hayes , Madhu Sudan , Yufei Zhao

We define $k$-dimensional digraphs and initiate a study of their spectral theory. The $k$-dimensional digraphs can be viewed as generating graphs for small categories called $k$-graphs. Guided by geometric insight, we obtain several new…

Operator Algebras · Mathematics 2022-11-08 Nadia S. Larsen , Alina Vdovina