Results 41 to 50 of about 1,186 (121)
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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A counterexample to a question of Bapat & Sunder
, 2018 The objective of this article is to provide a counterexample to a question of Bapat and Sunder concerning the relative magnitudes of the permanent of a positive semidefinite matrix and the largest eigenvalue of a related matrix.
S. Drury
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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
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Reversed determinantal inequalities for accretive-dissipative matrices
, 2012 A matrix A∈Mn(C) is said to be accretive-dissipative if, in its Toeplitz decomposition A = B+ iC , B = B∗ , C = C∗ , both matrices B and C are positive definite. Let A = [ A11 A12 A21 A22 ] be an accretive-dissipative matrix, k and l be the orders of A11
Minghua Lin
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On S-2-absorbing submodules and vn-regular modules
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2020 Let R be a commutative ring and M an R-module. In this article, we introduce the concept of S-2-absorbing submodule. Suppose that S ⊆ R is a multiplicatively closed subset of R.
Ulucak Gülşen, Tekir Ünsal, Koç Suat
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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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A real counterexample to two inequalities involving permanents
, 2017 The objective of this article is to provide a counterexample to the permanent version of Oppenheim’s inequality using real symmetric matrices. This also provides a countereample to the permanent on top conjecture for real symmetric positive semidefinite ...
S. Drury
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On the reverse Young and Heinz inequalities
, 2017 In this paper, we study further improvements of the reverse Young and Heinz inequalities for positive real numbers. We use these modified inequalities to obtain corresponding operator inequalities and matrix inequalities on the Hilbert–Schmidt norm ...
M. Ghaemi +2 more
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, 2016 A two-dimensional numerical study has been conducted to analyze forced convective confined flow and heat transfer from a pair of side-by-side square cylinders with a transverse gap ratio (defined as the ratio of the distance between the obstacles to the ...
A. Sanyal, A. Dhiman
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Fuzzy Integral domains and Fuzzy regular sequences
Open Journal of Mathematical Sciences, 2018 In this paper, the notions of fuzzy zero-divisors and fuzzy integral domains are illustrated. Some fundamental properties of fuzzy integral domains are proved. Moreover, the notions of fuzzy regular element and fuzzy regular sequences are defined.
Saba Ayub, Waqas Mahmood
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