Abstract
LetQ be a regular operator valued generalized Nevanlinna function with negative index κ, i.e.\(Q \in \mathcal{N}_\kappa (\mathcal{H})\). It is shown that then there exists a rational functionB(z), which collects the generalized poles and zeros ofQ that are not of positive type such that the function
belongs to the Nevanlinna class\(\mathcal{N}_0 (\mathcal{H})\).
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The author acknowledges support of the Fonds zur Förderung der wissenschaftlichen Forschung of Austria, Project P 12176 MAT, and of the EU Research Training Network, Contract No. HPRN-CT-2000-00116.