Growth estimates for sine-type-functions and applications to Riesz bases of exponentials
نویسنده
چکیده
We present explicit estimates for the growth of sine-type-functions as well as for the derivatives at their zero sets, thus obtaining explicit constants in a result of Levin. The estimates are then used to derive explicit lower bounds for exponential Riesz bases, as they arise in Avdonin’s Theorem on 1/4 in the mean or in a Theorem of Bogmér, Horváth, Joó and Seip. An application is discussed, where knowledge of explicit lower bounds of exponential Riesz bases is desirable.
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