Results 71 to 80 of about 1,618,968 (159)

On the Signless Laplacian Spectral Radius of Graphs without Small Books and Intersecting Quadrangles

Mathematics, 2022
In this paper, we determine the maximum signless Laplacian spectral radius of all graphs which do not contain small books as a subgraph and characterize all extremal graphs. In addition, we give an upper bound of the signless Laplacian spectral radius of
Ming-Zhu Chen, Ning Wang, A-Ming Liu, Aleksandr A. Makhnev   +3 more
doaj   +1 more source

A Note on the Spectral Radius of Weighted Signless Laplacian Matrix

Advances in Linear Algebra & Matrix Theory, 2018
A weighted graph is a graph that has a numeric label associated with each edge, called the weight of edge. In many applications, the edge weights are usually represented by nonnegative integers or square matrices. The weighted signless Laplacian matrix of a weighted graph is defined as the sum of adjacency matrix and degree matrix of same weighted ...
KAYA GÖK, GÜLİSTAN, BÜYÜKKÖSE, ŞERİFE, MUTLU, NURŞAH   +2 more
openaire   +3 more sources

The smallest eigenvalue of the signless Laplacian

, 2011
Recently the signless Laplacian matrix of graphs has been intensively investigated. While there are many results about the largest eigenvalue of the signless Laplacian, the properties of its smallest eigenvalue are less well studied.
Nikiforov, Vladimir, Oliveira, Carla Silva, Leonardo Silva de Lima, Vladimir Nikiforov, Nair Maria Maia de Abreu, Carla Silva Oliveira, De Abreu, Nair Maria Maia, De Lima, Leonardo Silva   +7 more
core   +1 more source

Signless Laplacian energy of interval-valued fuzzy graph and its applications [PDF]

, 2023
An interval-valued fuzzy graph (IVFG) emanates from a fuzzy graph (FG) where the membership is given in interval form. This framework give the user more flexibility in dealing with fuzzy information.
Al-Quran, Ashraf, Rashmanlou, Hossein, Nawawi, Athirah, Romdhini, Mamika Ujianita, Al-Sharqi, Faisal   +4 more
core   +1 more source

Signless Normalized Laplacian for Hypergraphs [PDF]

, 2021
The spectral theory of the normalized Laplacian for chemical hypergraphs is further investigated. The signless normalized Laplacian is introduced and it is shown that its spectrum for classical hypergraphs coincides with the spectrum of the normalized ...
Mulas, Raffaella, Andreotti, E., Andreotti, Eleonora, Mulas, R., Andreotti, Eleonora,, Mulas, Raffaella,   +5 more
core   +1 more source

Refined Lower Bounds for the Laplacian Estrada Index of Connected Graphs via the Two Largest Degrees

Journal of Mathematics, Volume 2026, Issue 1, 2026.
Let G be a graph with n vertices and Laplacian eigenvalues μ1, μ2, …, μn. The Laplacian Estrada index of G is defined as LEEG=eμ1+⋯+eμn. In this paper, using the Karush–Kuhn–Tucker optimization framework under inequality constraints, we establish new lower bounds for LEE(G) in terms of the two largest degrees of G.
Hamidreza Bamdad, Alireza Vahidi, Akram Mahmoodi, Smritijit Sen   +3 more
wiley   +1 more source

A sharp upper bound for the spectral radius of a nonnegative matrix and applications [PDF]

, 2011
summary:We obtain a sharp upper bound for the spectral radius of a nonnegative matrix. This result is used to present upper bounds for the adjacency spectral radius, the Laplacian spectral radius, the signless Laplacian spectral radius, the distance ...
Shu, Yujie, Zhang, Xiao-Dong, You, Lihua, YA-HONG CHEN, XIAO-DONG ZHANG, RONG-YING PAN   +5 more
core   +2 more sources

Construction of Albertson Cospectral and Albertson Equienergetic Graphs Using Graph Operations

Journal 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, Sabitha D’Souza, Swati Nayak, G Muhiuddin   +3 more
wiley   +1 more source

On the distance signless Laplacian spectral radius and the distance signless Laplacian energy of graphs

, 2018
The distance signless Laplacian spectral radius of a connected graph [Formula: see text] is the largest eigenvalue of the distance signless Laplacian matrix of [Formula: see text], defined as [Formula: see text], where [Formula: see text] is the distance
Abdollah Alhevaz, Somnath Paul, Maryam Baghipur   +2 more
core   +1 more source

Sufficient Conditions for Spanning k‐Hypertrees via Distance Spectral Radius of Hypergraphs

Journal of Mathematics, Volume 2026, Issue 1, 2026.
For an integer k ≥ 2, a spanning k‐hypertree T is defined as a spanning hypertree (β‐acyclic) such that the maximum degree dT(v) of every vertex v ∈ V(T) is at most k. A sufficient condition for the existence of a spanning k‐hypertree in connected hypergraphs is established.
Qiannan Niu, Jinyu Zou, Lei Zhang, Haizhen Ren, Zafar Ullah   +4 more
wiley   +1 more source