On the approximation properties of Cesàro means of negative order of double Vilenkin – Fourier series
DOI:
https://doi.org/10.37863/umzh.v72i3.6045Abstract
UDC 517.5
We establish approximation properties of Ces\`{a}ro means with α,β ϵ (0,1) of Vilenkin\,--\,Fourier series. This result allows one to obtain a condition which is sufficient for the convergence of the means σ−α,−βn,m(x,y,f) to f(x,y) in the Lp-metric.
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