Abstract:
The existence of functions the Fourier–Walsh series of which are universal in the sense of signs for the class of almost everywhere finite measurable functions, and the structure of such functions is described.
Keywords:universal functions, Fourier–Walsh series, convergence almost everywhere.
UDC:517.51
Presented:B. S. Kashin Received: 27.05.2020 Revised: 14.09.2020 Accepted: 28.11.2020