Natural Sciences, Mathematics, 2026
AN EXAMPLE OF DOUBLE FOURIER–HAAR SERIES WITH A NONREGULAR SUBSERIES
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Submitted: 2025-02-06
© 2026 by author(s) and The Gufo Inc.
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Abstract
We bring an example of integrable function on [0;1]2, so that the double Fourier–Haar series has a subseries, whose majorant of partial sums does not belong to L1,∞.