Computational Methods and Function Theory

, Volume 10, Issue 1, pp 281–289 | Cite as

The Hadamard Product as a Universality Preserving Operator

  • Jürgen Müller
  • Timo Pohlen


Let ψ be holomorphic in a domain containing 0 and ∞, and φ a function that has a universal Taylor series with respect to 0. We consider the question whether the Hadamard product ψ * φ has a similar universality property.


Hadamard product universal series overconvergence lacunary approximation 

2000 MSC

30B 30E10 


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Copyright information

© Heldermann  Verlag 2010

Authors and Affiliations

  1. 1.Department of MathematicsUniversity of Trier, Fachbereich IVTrierGermany

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