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Related papers: Spectra of Corona Products of Digraphs

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This paper introduces four types of subdivision products for simple directed graphs extending those from the undirected case, in particular, the subdivision-vertex join, subdivision-arc join, subdivision-vertex corona and subdivision-arc…

Combinatorics · Mathematics 2026-05-22 Michael Cavers , Farzad Maghsoudi , Babak Miraftab

Product graphs have been gainfully used in literature to generate mathematical models of complex networks which inherit properties of real networks. Realizing the duplication phenomena imbibed in the definition of corona product of two…

Spectral Theory · Mathematics 2015-07-21 Rohan Sharma , Bibhas Adhikari , Abhishek Mishra

In this paper, we introduce a generalization of corona of graphs. This construction generalizes the generalized corona of graphs (consequently, the corona of graphs), the cluster of graphs, the corona-vertex subdivision graph of graphs and…

Combinatorics · Mathematics 2020-08-13 R. Rajkumar , M. Gayathri

In this paper, we extend our earlier proposal of corona product of signed graphs into generalized corona product of signed graphs inspired by the generalized corona product of unsigned graphs. Then we study structural balance and spectral…

Combinatorics · Mathematics 2023-10-13 Amrik Singh , Ravi Srivastava , Bibhas Adhikari , Sandeep Kumar Yadav

This paper introduces the concept of $\mu$-signed and duplication signed graphs and shows that both are always structurally balanced. Using the duplication signed graph, we define the corona product of the duplication signed graph…

Combinatorics · Mathematics 2025-10-31 Bishal Sonar , Ravi Srivastava

We introduce a new invariant, the coronal of a graph, and use it to compute the spectrum of the corona $G\circ H$ of two graphs $G$ and $H$. In particular, we show that this spectrum is completely determined by the spectra of $G$ and $H$…

Combinatorics · Mathematics 2011-11-07 Cam McLeman , Erin McNicholas

For unsigned graphs G and H, the characteristic polynomial of different graph matrices for edge corona, subdivision vertex neighbourhood corona and subdivision edge neighbourhood corona has already been studied using the concept of coronal.…

Combinatorics · Mathematics 2024-01-11 Satyam Guragain , Ravi Srivastava , Bishal Sonar

In this paper, we introduce central vertex corona, central edge corona, and central edge neighborhood corona of graphs using central graph. Also, we determine their adjacency spectrum, Laplacian spectrum and signless Laplacian spectrum.…

Combinatorics · Mathematics 2021-12-28 T K Jahfar , A V Chithra

A unified approach to the determination of eigenvalues and eigenvectors of specific matrices associated with directed graphs is presented. Matrices studied include the distance matrix, distance Laplacian, and distance signless Laplacian, in…

Combinatorics · Mathematics 2020-08-04 Minerva Catral , Lorenzo Ciardo , Leslie Hogben , Carolyn Reinhart

In this paper, we determine the two normalized Laplacian spectrum of generalized subdivision- vertex corona, subdivision-edge corona for a connected regular graph with an arbitrary reg- ular graph in terms of their normalized Laplacian…

Combinatorics · Mathematics 2018-07-12 Qun Liu , Zhongzhi Zhang

Let $G_1$ and $G_2$ be two simple connected graphs. The invariant \textit{coronal} of graph is used in order to determine the $\alpha$-eigenvalues of four different types of graph equations that are $G_1 \circ G_2, G_1\lozenge G_1$ and the…

Combinatorics · Mathematics 2020-08-05 Muhammad Ateeq Tahir , Xiao-Dong Zhang

Many graph products have been applied to generate complex networks with striking properties observed in real-world systems. In this paper, we propose a simple generative model for simplicial networks by iteratively using edge corona…

Discrete Mathematics · Computer Science 2020-02-28 Yucheng Wang , Yuhao Yi , Wanyue Xu , Zhongzhi Zhang

The notion of corona of two graphs was introduced by Frucht and Harary in 1970. In this paper we generalize their definition of corona product of two graphs and introduce corona product of two signed graphs by utilizing the framework of…

Combinatorics · Mathematics 2019-08-28 Bibhas Adhikari , Amrik Singh , Sandeep Kumar Yadav

The paper focuses on studying strong geodetic sets and numbers in the context of corona-type products of graphs. Our primary focus is on three variations of the corona products: the generalized corona, generalized edge corona, and…

Combinatorics · Mathematics 2024-11-21 Bishal Sonar , Satyam Guragain , Ravi Srivastava

The $T$-graph $T(G)$ of a graph $G$ is the graph whose vertices are the vertices and edges of $G$, with two vertices of $T(G)$ are adjacent if and only if the corresponding elements of $G$ are adjacent or incident. In this paper, we…

Combinatorics · Mathematics 2025-09-17 Indranil Mukherjee , Suvra Kanti Chakraborty , Arpita Das

Given simple graphs $G_1$ and $G_2$, the neighbourhood corona of $G_1$ and $G_2$, denoted $G_1\star G_2$, is the graph obtained by taking one copy of $G_1$ and $|V(G_1)|$ copies of $G_2$, and joining the neighbours of the $i$th vertex of…

Combinatorics · Mathematics 2014-10-03 Xiaogang Liu , Sanming Zhou

The corona of hypergraphs is an extension of the corona operation applied to graphs. The corona $G_0^* \odot_1^n G_1^*$ of two hypergraphs is obtained by taking $n$ copies of $G_1^*$ (where $n$ is the order of $G_0^*$) and by joining the…

Combinatorics · Mathematics 2024-03-06 Liya Jess Kurian , Chithra A.

We introduce recursive corona graphs as a model of small-world networks. We investigate analytically the critical characteristics of the model, including order and size, degree distribution, average path length, clustering coefficient, and…

Discrete Mathematics · Computer Science 2016-01-27 Qian Lv , Yuhao Yi , Zhongzhi Zhang

For simple graphs $G$, $G_1$ and $G_2$, we denote their double corona based on $R$-graph by $G^{(R)}\otimes{\{G_1,G_2\}}$. This paper determines the normalized Laplacian spectrum of $G^{(R)}\otimes{\{G_1,G_2\}}$ in terms of these of $G$,…

Combinatorics · Mathematics 2017-09-11 Ping-Kang Yu , Gui-Xian Tian

Let $G=(V(G),E(G))$ be a graph with vertex set $V(G)$ and edge set $E(G)$. The subdivision graph $\mathcal{S}(G)$ of a graph $G$ is the graph obtained by inserting a new vertex into every edge of $G$. Let $G_1$ and $G_2$ be two vertex…

Combinatorics · Mathematics 2014-07-29 Xiaogang Liu , Pengli Lu
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