Theory of Computing Systems

, Volume 46, Issue 2, pp 340–350 | Cite as

Computing Interpolating Sequences



Naftalevič’s Theorem states that, given a Blaschke sequence, it is possible to modify the arguments of its terms so as to obtain an interpolating sequence. We prove a computable version of this theorem in that it possible, given a Blaschke sequence, to computably modify the arguments of its terms so as to obtain an interpolating sequence. Using this result, we produce a computable, interpolating Blaschke sequence that does not define a computable Blaschke product. This answers a question posed by Matheson and McNicholl in a recent paper. We use Type-Two Effectivity as our foundation.


Computable analysis Complex analysis 


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© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  1. 1.Department of MathematicsLamar UniversityBeaumontUSA

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