Bounded Functions and Fourier Transforms
نویسندگان
چکیده
1. Statement of the principal result. The class of sequences obtainable as Fourier coefficients of measures on the circle group presents numerous structure problems of interest. Amongst the earliest results somewhat akin to that stated below appear Banach's theorems about lacunary coefficients; see e.g., [4, pp. 215-220]. More recently Helson [3] has studied analogous questions when the group concerned is the real line. The aim of the present paper is to give a simple proof by abstract methods of the following
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