Computable analysis and Blaschke products

Matheson, Alec; McNicholl, Timothy

doi:10.1090/S0002-9939-07-09102-2

Computable analysis and Blaschke products
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by Alec Matheson and Timothy H. McNicholl PDF

Proc. Amer. Math. Soc. 136 (2008), 321-332 Request permission

Abstract:

We show that if a Blaschke product defines a computable function, then it has a computable sequence of zeros in which the number of times each zero is repeated is its multiplicity. We then show that the converse is not true. We finally show that every computable, radial, interpolating sequence yields a computable Blaschke product.

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