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Remarks on Inner Functions and Optimal Approximants

  • Catherine Bénéteau (a1), Matthew C. Fleeman (a2), Dmitry S. Khavinson (a3), Daniel Seco (a4) and Alan A. Sola (a5)...

We discuss the concept of inner function in reproducing kernelHilbert spaces with an orthogonal basis of monomials and examine connections between inner functions and optimal polynomial approximants to 1/f, where f is a function in the space. We revisit some classical examples from this perspective, and show how a construction of Shapiro and Shields can be modiûed to produce inner functions.

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Canadian Mathematical Bulletin
  • ISSN: 0008-4395
  • EISSN: 1496-4287
  • URL: /core/journals/canadian-mathematical-bulletin
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