Results 21 to 30 of about 340,902 (280)
Graphs with eigenvalues at least −2
Linear Algebra and its Applications, 1982 AbstractThe family of minimal forbidden graphs for the set of graphs with all eigenvalues at least −2 is described. It is shown that each minimal forbidden graph has at most 10 vertices and the bound is the best possible.
Kumar, Vijaya, Rao, S.B., Singhi, N.M.
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Characterization of the Minimizing Graph of the Connected Graphs Whose Complements Are Bicyclic
Mathematics, 2017 In a certain class of graphs, a graph is called minimizing if the least eigenvalue of its adjacency matrix attains the minimum. A connected graph containing two or three cycles is called a bicyclic graph if its number of edges is equal to its number of ...
Muhammad Javaid
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Robust Adaptive Identification of Linear Time-Varying Systems Under Relaxed Excitation Conditions
IEEE Access, 2020 An on-line modified least-squares identification algorithm is proposed for linear time-varying systems with bounded disturbances under relaxed excitation conditions.
Yifei Hu, Jinbo Wu, Chenghao Zeng
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Nonlinear mappings preserving at least one eigenvalue [PDF]
Studia Mathematica, 2010 We prove that if $F$ is a Lipschitz map from the set of all complex $n\times n$ matrices into itself with $F(0)=0$ such that given any $x$ and $y$ we have that $% F\left( x\right) -F\left( y\right) $ and $x-y$ have at least one common eigenvalue, then either $F\left( x\right) =uxu^{-1}$ or $F\left( x\right) =ux^{t}u^{-1}$ for all $x$, for some ...
Costara, Constantin, Repovš, Dušan
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Balancedness and the Least Laplacian Eigenvalue of Some Complex Unit Gain Graphs
Discussiones Mathematicae Graph Theory, 2020 Let 𝕋4 = {±1, ±i} be the subgroup of 4-th roots of unity inside 𝕋, the multiplicative group of complex units. A complex unit gain graph Φ is a simple graph Γ = (V (Γ) = {v1, . . .
Belardo Francesco +2 more
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Examples and Counterexamples, 2022 We continue the investigation on the spectrum of operators arising from the discretization of partial differential equations. In this paper we consider a three field formulation recently introduced for the finite element least-squares approximation of ...
Linda Alzaben +2 more
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Inverse Eigenvalue Problem and Least-Squares Problem for Skew-Hermitian {P,K + 1}-Reflexive Matrices
Journal of Mathematics, 2022 This paper involves related inverse eigenvalue problem and least-squares problem of skew-Hermitian {P,k + 1}-reflexive(antireflexive) matrices and their optimal approximation problems.
Chang-Zhou Dong, Hao-Xue Li
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Least eigenvalue of the connected graphs whose complements are cacti
Open Mathematics, 2019 Suppose that Γ is a graph of order n and A(Γ) = [ai,j] is its adjacency matrix such that ai,j is equal to 1 if vi is adjacent to vj and ai,j is zero otherwise, where 1 ≤ i, j ≤ n.
Wang Haiying +4 more
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On Least Distance Eigenvalue of Uniform Hypergraphs
Taiwanese Journal of Mathematics, 2018 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Lin, Hongying, Zhou, Bo
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On the eigenvalues of firefly graphs [PDF]
Transactions on Combinatorics, 2014 The sharp upper bounds and the sharp lower bounds of the largest eigenvalues $lambda_1$, the least eigenvalue $lambda_n$, the second largest eigenvalue $lambda_2$, the spread and the separator among all firefly graphs on $n$ vertices are determined.
Hong Wenxi, You Lihua
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