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Related papers: Spectral study of alliances in graphs

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Learning a graph with a specific structure is essential for interpretability and identification of the relationships among data. It is well known that structured graph learning from observed samples is an NP-hard combinatorial problem. In…

Machine Learning · Statistics 2019-09-26 Sandeep Kumar , Jiaxi Ying , Jos'e Vin'icius de M. Cardoso , Daniel P. Palomar

Graph Laplacians on finite compact metric graphs are considered under the assumption that the matching conditions at the graph vertices are of either $\delta$ or $\delta'$ type. In either case, an infinite series of trace formulae which…

Mathematical Physics · Physics 2014-04-01 Yulia Ershova , Alexander V. Kiselev

We present enumeration results on the number of connected graphs up to 10 vertices for which there is at least one other graph with the same spectrum (a cospectral mate), or at least one other graph with the same Smith normal form…

Combinatorics · Mathematics 2020-08-14 Aida Abiad , Carlos A. Alfaro

The power graph $P(\Omega)$ of a group $\Omega$ is a graph with the vertex set $\Omega$ such that two distinct vertices form an edge if and only if one of them is an integral power of the other. In this article, we determine the power graph…

Combinatorics · Mathematics 2022-10-03 Yogendra Singh , Anand Kumar Tiwari , Fawad Ali

Distinctive power of the alliance polynomial has been studied in previous works, for instance, it has been proved that the empty, path, cycle, complete, complete without one edge and star graphs are characterized by its alliance polynomial.…

Combinatorics · Mathematics 2020-01-07 Walter Carballosa , Omar Rosario , José M. Sigarreta , Yadira Torres-Nuñez

In this article, we introduce a geometric and a spectral preorder relation on the class of weighted graphs with a magnetic potential. The first preorder is expressed through the existence of a graph homomorphism respecting the magnetic…

Combinatorics · Mathematics 2022-07-11 John Stewart Fabila-Carrasco , Fernando Lledó , Olaf Post

The vertex-weighted Laplacian naturally extends the combinatorial Laplacian for simplicial complexes. Inspired by Lew's foundational techniques for vertex-weighted Laplacians, we present a comprehensive spectral analysis of this operator.…

Combinatorics · Mathematics 2025-12-12 Yueli Han , Lu Lu

Complex networks or graphs are ubiquitous in sciences and engineering: biological networks, brain networks, transportation networks, social networks, and the World Wide Web, to name a few. Spectral graph theory provides a set of useful…

Statistics Theory · Mathematics 2019-01-23 Subhadeep Mukhopadhyay , Kaijun Wang

We study connected graphs with a fixed degree sequence, in the sparse setting where the number of edges grows linearly in the number of vertices. Using the relation to the configuration model, we identify the number of such connected graphs…

Combinatorics · Mathematics 2026-05-11 Sasha Bell , Serte Donderwinkel , Remco van der Hofstad

In this paper, we examine covering graphs that are obtained from the $d$-dimensional integer lattice by adding pendant edges. In the case of $d=1$, we show that the Laplacian on the graph has a spectral gap and establish a necessary and…

Mathematical Physics · Physics 2013-04-17 Aktito Suzuki

We consider symmetric powers of a graph. In particular, we show that the spectra of the symmetric square of strongly regular graphs with the same parameters are equal. We also provide some bounds on the spectra of the symmetric squares of…

Combinatorics · Mathematics 2007-05-23 Koenraad Audenaert , Chris Godsil , Gordon Royle , Terry Rudolph

In finite group theory, studying the prime graph of a group has been an important topic for almost the past half-century. Recently, prime graphs of solvable groups have been characterized in graph theoretical terms only. This now allows the…

Combinatorics · Mathematics 2020-11-19 Chris Florez , Jonathan Higgins , Kyle Huang , Thomas Michael Keller , Dawei Shen

We determine all graphs whose adjacency matrix has at most two eigenvalues (multiplicities included) different from $\pm 1$ and decide which of these graphs are determined by their spectrum. This includes the so-called friendship graphs,…

Combinatorics · Mathematics 2013-10-25 Sebastian M. Cioabă , Willem H. Haemers , Jason Vermette , Wiseley Wong

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

In the paper we give a lower bound for the number of vertices of a given graph using its chromatic number. We find the graphs for which this bound is exact. The results are applied in the theory of Foklman numbers.

Combinatorics · Mathematics 2010-02-24 Nedyalko Dimov Nenov

Algebraic connectivity is one way to quantify graph connectivity, which in turn gauges robustness as a network. In this paper, we consider the problem of maximising algebraic connectivity both local and globally over all simple, undirected,…

Combinatorics · Mathematics 2024-06-11 Karim Shahbaz , Madhu N. Belur , Ajay Ganesh

We study the secure domination number of the Mycielskian graph of a simple, connected, undirected graph. We give generally applicable bounds, compute secure domination numbers for Mycielskians of important families of graphs, and construct…

Combinatorics · Mathematics 2026-03-19 Kiran R. Bhutani , Anthony Christiana , Peter Ulrickson

Graph is an abstract representation commonly used to model networked systems and structure. In problems across various fields, including computer vision and pattern recognition, and neuroscience, graphs are often brought into comparison (a…

Optimization and Control · Mathematics 2022-03-04 Quoc Van Tran , Hyo-Sung Ahn

We present a novel theoretical framework connecting k-component edge connectivity with spectral graph theory and homology theory to pro vide new insights into the resilience of real-world networks. By extending classical edge connectivity…

Combinatorics · Mathematics 2024-09-10 Joshua Steier

The Bell numbers count the number of different ways to partition a set of $n$ elements while the graphical Bell numbers count the number of non-equivalent partitions of the vertex set of a graph into stable sets. This relation between graph…

Discrete Mathematics · Computer Science 2024-03-11 Alain Hertz , Anaelle Hertz , Hadrien Mélot