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Laplacian and signless laplacian spectra and energies of multi-step wheels

open access: yesMathematical Biosciences and Engineering, 2020
<abstract> <p>Energies and spectrum of graphs associated to different linear operators play a significant role in molecular chemistry, polymerisation, pharmacy, computer networking and communication systems. In current article, we compute closed forms of signless Laplacian and Laplacian spectra and energies of multi-step wheel networks < ...
Zheng-Qing Chu   +4 more
openaire   +4 more sources

Spectra of the neighbourhood corona of two graphs

open access: yes, 2013
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 $G_1$ to every ...
Liu, Xiaogang, Zhou, Sanming
core   +1 more source

Characterizing an odd [1, b]-factor on the distance signless Laplacian spectral radius

open access: yesRAIRO Oper. Res., 2023
Let G be a connected graph of even order n. An odd [1,b]-factor of G is a spanning subgraph F of G such that dF(v) ∈ {1,3,5,··· ,b} for any v ∈ V (G), where b is positive odd integer.
Sizhong Zhou, Hong-xia Liu
semanticscholar   +1 more source

Laplacian matrices of weighted digraphs represented as quantum states

open access: yes, 2017
Representing graphs as quantum states is becoming an increasingly important approach to study entanglement of mixed states, alternate to the standard linear algebraic density matrix-based approach of study.
Adhikari, Bibhas   +3 more
core   +1 more source

Sharp Bounds for the Signless Laplacian Spectral Radius in Terms of Clique Number [PDF]

open access: yes, 2012
In this paper, we present a sharp upper and lower bounds for the signless Laplacian spectral radius of graphs in terms of clique number. Moreover, the extremal graphs which attain the upper and lower bounds are characterized.
Abraham Berman   +5 more
core  

The extremal spectral radii of $k$-uniform supertrees

open access: yes, 2014
In this paper, we study some extremal problems of three kinds of spectral radii of $k$-uniform hypergraphs (the adjacency spectral radius, the signless Laplacian spectral radius and the incidence $Q$-spectral radius). We call a connected and acyclic $k$
Li, Honghai, Qi, Liqun, Shao, Jiayu
core   +1 more source

Inequalities for Distance Signless Laplacian Matrix Under Minimum‐Degree Constraints

open access: yesJournal of Mathematics, Volume 2026, Issue 1, 2026.
For a connected graph G of order n, let D(G) denote its distance matrix and let Tr(G) be the diagonal matrix formed by the vertex transmissions. The distance signless Laplacian of G is defined by DQ = D(G) + Tr(G). The largest eigenvalue of DQ, written as ∂1QG, is referred to as the distance signless Laplacian spectral radius of G.
Mohd Abrar Ul Haq   +3 more
wiley   +1 more source

On the spectral radius of a class of non-odd-bipartite even uniform hypergraphs

open access: yes, 2015
In order to investigate the non-odd-bipartiteness of even uniform hypergraphs, starting from a simple graph $G$, we construct a generalized power of $G$, denoted by $G^{k,s}$, which is obtained from $G$ by blowing up each vertex into a $k$-set and each ...
Fan, Yi-Zheng, Khan, Murad-ul-Islam
core   +1 more source

Construction of Albertson Cospectral and Albertson Equienergetic Graphs Using Graph Operations

open access: yesJournal of Mathematics, Volume 2026, Issue 1, 2026.
The energy of a graph is an invariant calculated as the sum of the absolute eigenvalues of its adjacency matrix. This concept extends to various types of energies derived from different graph‐related matrices. This paper explores the spectral properties of Albertson energy and Albertson spectra.
Jane Shonon Cutinha   +3 more
wiley   +1 more source

The Largest Laplacian and Signless Laplacian H-Eigenvalues of a Uniform Hypergraph [PDF]

open access: yes, 2013
In this paper, we show that the largest Laplacian H-eigenvalue of a $k$-uniform nontrivial hypergraph is strictly larger than the maximum degree when $k$ is even. A tight lower bound for this eigenvalue is given.
Hu, Shenglong, Qi, Liqun, Xie, Jinshan
core  

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