A Universal Constant for Exponential Riesz Sequences
نویسنده
چکیده
The aim of this paper is to study certain correlations between lower and upper bounds of exponential Riesz sequences, in particular between sharp lower and upper bounds, where we show that the product of the sharp bounds of an exponential Riesz sequence is bounded from above by a universal constant. The result is applied to the norms of coefficient and frame operators and their inverses.
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