Перегляд за автором "Zagorodnyuk, S.M."

Сортувати за: Порядок: Результатів:

  • Integral Representations for Spectral Functions of Some Nonself-Adjoint Jacobi Matrices 
    Zagorodnyuk, S.M. (2009)
    We study a Jacobi matrix J with complex numbers an, n belongs Z+, in the main diagonal such that r0 ≤ Im an ≤ r1, r0, r1 belongs Z+. We obtain an integral representation for the (generalized) spectral function of the matrix ...
  • On the Complex Symmetric and Skew-Symmetric Operators with a Simple Spectrum 
    Zagorodnyuk, S.M. (Symmetry, Integrability and Geometry: Methods and Applications, 2011)
    In this paper we obtain necessary and sufficient conditions for a linear bounded operator in a Hilbert space H to have a three-diagonal complex symmetric matrix with non-zero elements on the first sub-diagonal in an ...
  • Orthogonal Polynomials on Rays: Properties of Zeros, Related Moment Problems and Symmetries 
    Zagorodnyuk, S.M. (Журнал математической физики, анализа, геометрии, 2008)
    We establish some basic properties of zeros for orthonormal polynomials on radial rays. We introduce a moment problem related to these orthonormal polynomials and obtain necessary and sufficient conditions for its solvability. ...
  • The Inverse Spectral Problem for Jacobi-Type Pencils 
    Zagorodnyuk, S.M. (Symmetry, Integrability and Geometry: Methods and Applications, 2017)
    In this paper we study the inverse spectral problem for Jacobi-type pencils. By a Jacobi-type pencil we mean the following pencil J₅−λJ₃, where J₃ is a Jacobi matrix and J₅ is a semi-infinite real symmetric five-diagonal ...