APPROXIMATION IN ORLICZ-STEPANETS SPACES DEFINED BY VILENKIN-FOURIER COEFFICIENTS
摘要
Direct and inverse theorems of approximation in Orlicz-Stepanets spaces are given in two forms: for modulus of continuity defined by a generalized translation and K-functional of arbitrary order defined by a generalized derivative. Several equivalence theorems connected with an above modulus of continuity or K-functional and Riesz-Zygmund means of Vilenkin-Fourier series are obtained.