Results 21 to 30 of about 966 (119)
Diagonal dominance and invertibility of matrices
Special Matrices, 2023 A weakly diagonally dominant matrix may or may not be invertible. We characterize, in terms of combinatorial structure and sign pattern when such a matrix is invertible, which is the common case. Examples are given.
Johnson Charles Royal +2 more
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An inequality for means with applications
, 2008 We show that an almost trivial inequality for the first and second mean of a random variable can be used to give non-trivial improvements on deep results. As applications we improve on results on lower bounds for the Riemann zeta-function on the critical
Schlage-Puchta, Jan-Christoph
core +1 more source
The bipartite Laplacian matrix of a nonsingular tree
Special Matrices, 2023 For a bipartite graph, the complete adjacency matrix is not necessary to display its adjacency information. In 1985, Godsil used a smaller size matrix to represent this, known as the bipartite adjacency matrix.
Bapat Ravindra B. +2 more
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An extension and a generalization of Dedekind's theorem
, 2016 For any given finite abelian group, we give factorizations of the group determinant in the group algebra of any subgroup. The factorizations are an extension of Dedekind's theorem.
Yamaguchi, Naoya
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Remarks on the $\alpha$--permanent
, 2009 We recall Vere-Jones's definition of the $\alpha$--permanent and describe the connection between the (1/2)--permanent and the hafnian. We establish expansion formulae for the $\alpha$--permanent in terms of partitions of the index set, and we use these ...
Frenkel, Péter E.
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Characteristic polynomial, determinant and inverse of a Fibonacci-Sylvester-Kac matrix
Special Matrices, 2021 In this paper, we consider a new Sylvester-Kac matrix, i.e., Fibonacci-Sylvester-Kac matrix. We discuss the eigenvalues, eigenvectors and characteristic polynomial of this matrix in two categories based on whether the Fibonacci-Sylvester-Kac matrix order
Jiang Zhaolin, Zheng Yanpeng, Li Tianzi
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Generalized Gram–Hadamard inequality [PDF]
, 2010 We generalize the classical Gram determinant inequality. Our generalization follows from the boundedness of the antisymmetric tensor product operator.
Constantinescu, Florin (Prof. Dr.) +1 more
core
A determinant characterization of moment sequences with finitely many mass-points
, 2014 To a sequence (s_n)_{n\ge 0} of real numbers we associate the sequence of Hankel matrices \mathcal H_n=(s_{i+j}),0\le i,j \le n. We prove that if the corresponding sequence of Hankel determinants D_n=\det\mathcal H_n satisfy D_n>0 for ...
Berg, Christian, Szwarc, Ryszard
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Veterinary Dermatology, Volume 37, Issue 3, Page 353-364, June 2026.ABSTRACT Background Canine atopic dermatitis (cAD) is a multifactorial, inherited skin disease, estimated to affect ≤ 15% of dogs. Studies of skin messenger mRNA in cAD currently use invasive methods, including blood sampling and biopsy collection, whilst advances in human atopic dermatitis study methodology have demonstrated reliable use of minimally ...
Xavier Langon +5 more
wiley +1 more source
A counterexample to the Drury permanent conjecture
Special Matrices, 2017 We offer a counterexample to a conjecture concerning the permanent of positive semidefinite matrices. The counterexample is a 4 × 4 complex correlation matrix.
Hutchinson George
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