Results 1 to 10 of about 43 (41)
A note on the structure of normal Hamiltonian matrices
Operators and Matrices, 2021 The structures of the blocks of a normal Hamiltonian matrix are studied. In this note it is obtained that all four blocks of a normal Hamiltonian matrix H = [ A B C −A∗ ] can be expressed as linear combinations of four other matrices. Mathematics subject
C. Chorianopoulos
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Singular matrices that are products of two idempotents or products of two nilpotents
Special Matrices, 2021 Over commutative domains we characterize the singular 2 × 2 matrices which are products of two idempotents or products of two nilpotents. The relevant casees are the matrices with zero second row and the singular matrices with only nonzero entries.
Călugăreanu Grigore
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Combined matrix of diagonally equipotent matrices
Special Matrices, 2023 Let C(A)=A∘A−T{\mathcal{C}}\left(A)=A\circ {A}^{-T} be the combined matrix of an invertible matrix AA, where ∘\circ means the Hadamard product of matrices.
Bru Rafael +4 more
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Special Matrices, 2021 We propose an algorithm, which is based on the method given by Kişi and Özdemir in [Math Commun, 23 (2018) 61], to handle the problem of when a linear combination matrix X=∑i=1mciXiX = \sum\nolimits_{i = 1}^m {{c_i}{X_i}} is a matrix such that its ...
Kişi Emre +3 more
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Algebraic conditions and the sparsity of spectrally arbitrary patterns
Special Matrices, 2021 Given a square matrix A, replacing each of its nonzero entries with the symbol * gives its zero-nonzero pattern. Such a pattern is said to be spectrally arbitrary when it carries essentially no information about the eigenvalues of A.
Deaett Louis, Garnett Colin
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Schrödinger’s tridiagonal matrix
Special Matrices, 2021 In the third part of his famous 1926 paper ‘Quantisierung als Eigenwertproblem’, Schrödinger came across a certain parametrized family of tridiagonal matrices whose eigenvalues he conjectured.
Kovačec Alexander
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, 2020 Let T = T (n1,n2, · · · ,nk) ⊆ Mn(C ) be a block upper triangular matrix algebra and let M be a 2-torsion free unital T -bimodule, where C is a commutative ring. Let Δ : T →M be a C -linear map. We show that if Δ(X)Y +XΔ(Y)+Δ(Y)X +YΔ(X) = 0 whenever X ,Y
H. Ghahramani +2 more
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The expected adjacency and modularity matrices in the degree corrected stochastic block model
Special Matrices, 2018 We provide explicit expressions for the eigenvalues and eigenvectors of matrices that can be written as the Hadamard product of a block partitioned matrix with constant blocks and a rank one matrix.
Fasino Dario, Tudisco Francesco
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k-Jacobsthal and k-Jacobsthal Lucas Matrix Sequences
, 2016 In this study, we consider sequences named k-Jacobsthal, k-Jacobsthal Lucas sequences. After that, by using these sequences, we dene kJacobsthal and k-Jacobsthal-Lucas matrix sequence at the same time.
S. Uygun, H. Eldogan
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, 2015 We present an approximate solution depending on collocation method and Bernstein polynomials for numerical solution of a singular nonlinear differential equations with the mixed conditions.
M. Alshbool +3 more
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