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Menshov representation spectra

Gady Kozma·Alexander Olevskii
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Abstract

A Menshov spectrum is a subset of the integers that is sufficient for representing every measurable function as an almost-everywhere converging trigonometric (non-Fourier) sum. In this language the celebrated "Menshov representation theorem" states that Z is a Menshov spectrum. In this paper we construct 1) Menshov spectra that are almost exponentially sparse 2) that are almost squares. Then we show that the positive integers are not a Menshov spectrum but are a Menshov spectrum in measure, and repeat 1) and 2) in the analytic settings.

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Gady Kozma, Alexander Olevskii. 2005-10-28. Menshov representation spectra. https://arxiv.org/abs/math/0510616

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