Integral Equations and Operator Theory

, Volume 36, Issue 1, pp 121–125

A factorization result for generalized Nevanlinna functions of the classNk

  • A. Dijksma
  • H. Langer
  • A. Luger
  • Yu. Shondin
Article

Abstract

LetQNk. It is shown that if α is a nonreal pole or a real generalized pole of nonpositive type and β is a nonreal zero or a real generalized zero of nonpositive type of the functionQ then the function
$$Q_1 (z): = \frac{{(z - \alpha )(z - \bar \alpha )}}{{(z - \beta )(z - \bar \beta )}}Q(z)$$
belongs to the classNk−1.

ASM Classification Numbers

30D50 30E99 47B50 

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References

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Copyright information

© Birkhäuser Verlag 2000

Authors and Affiliations

  • A. Dijksma
    • 1
  • H. Langer
    • 3
  • A. Luger
    • 3
  • Yu. Shondin
    • 2
  1. 1.Department of MathematicsGroningenThe Netherlands
  2. 2.Department of Theoretical PhysicsState Pedagogical UniversityNizhny NovgorodRussia
  3. 3.Institut für Analysis und Technische MathematikTechnische Universität WienWienAustria

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