Search Results - "Kovalyov, Ivan"

Darboux transformation of symmetric Jacobi matrices and Toda lattices by Kovalyov, Ivan, Levina, Oleksandra

“…Let J be a symmetric Jacobi matrix associated with some Toda lattice. We find conditions for Jacobi matrix J to admit factorization J = LU (or J = ) with L (or…”
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Shifted Darboux Transformations of the Generalized Jacobi Matrices, I by Kovalyov, Ivan M.

“…Let ℑ be a monic generalized Jacobi matrix, i.e., a three-diagonal block matrix of a special form. We find conditions for a monic generalized Jacobi matrix ℑ…”
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Darboux transformation with parameter of generalized Jacobi matrices by Kovalyov, Ivan M.

“…A monic generalized Jacobi matrix J is factorized into upper and lower triangular two-diagonal block matrices of special forms so that J = UL . It is shown…”
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A truncated indefinite Stieltjes moment problem by Kovalyov, Ivan

“…A truncated indefinite Stieltjes moment problem in the class N κ k of generalized Stieltjes functions is studied. The set of solutions of the Stieltjes moment…”
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Darboux Transformation of the Laguerre Operator by Kovalyov, Ivan

“…Let L α be a Laguerre operator with α ∉ Z - = { - 1 , - 2 , … } . Constructing the pairs of the factorization operators L , R or L , R such that L α = LR or L…”
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The Schur algorithm for an indefinite Stieltjes moment problem by Derkach, Volodymyr, Kovalyov, Ivan

“…The nondegenerate truncated indefinite Stieltjes moment problem in the class Nκk of generalized Stieltjes functions is considered. To describe the set of…”
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An operator approach to the indefinite Stieltjes moment problem by Derkach, Vladimir, Kovalyov, Ivan

“…A function f meromorphic on ℂ\ℝ is said to be in the generalized Nevanlinna class N κ ( κ ϵ ℤ + ), if f is symmetric with respect to ℝ and the kernel N ω z ≔ f…”
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Rational generalized Stieltjes functions by Kovalyov, Ivan

“…The rational meromorphic functions on $\mathbb{C}\backslash\mathbb{R}$ are studied. We consider the some classes of one, as the generalized Nevanlinna…”
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Two-dimensional moment problem and Schur algorithm by Kovalyov, Ivan, Kunis, Stefan

“…We study a truncated two-dimensional moment problem in terms of the Stieltjes transform. The set of the solutions is described by the Schur step-by-step…”
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Uncertainty product for Vilenkin groups by Kovalyov, Ivan, Lebedeva, Elena

“…We study a localization of functions defined on Vilenkin groups. To measure the localization we introduce two uncertainty products $UP_{\lambda}$ and $UP_{G}$…”
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Schur algorithm for Stieltjes indefinite moment problem by Derkach, Vladimir, Kovalyov, Ivan

“…Nondegenerate truncated indefinite Stieltjes moment problem in the class $\mathbf{N}_{\kappa}^{k}$ of generalized Stieltjes functions is considered. To…”
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