21 citations · 37 across the 5 of their papers we have counts for
5 papers
Uniform approximation of periodical functions by trigonometric sums of a special type
A. S. Serdyuk, Ie. Yu. Ovsii
The approximation properties of the trigonometric sums U_{n,p}^ψof a special type are investigated on the classes C^ψ_{β, \infty} of (ψ,β)-differentiable (in the sense of Stepanets…
Approximation of continuous periodic functions by de la Vallee Poussin sums
Ie. Yu. Ovsii, A. S. Serdyuk
We obtain an estimate of the deviation of de la Vallee Poussin sums V_{n,n/2}(f;x) from continuous functions f, expressed in terms of values of theirs modulus of continuity. It is…
Approximation of classes of analytic functions by de la Vallee Poussin sums in uniform metric
A. S. Serdyuk, Ie. Yu. Ovsii, A. P. Musienko
In this paper asymptotic equalities are found for the least upper bounds of deviations in the uniform metric of de la Vallee Poussin sums on classes of 2π-periodic (ψ,β)-differenti…
Uniform approximation of Poisson integrals of functions from the class H_omega by de la Vallee Poussin sums
A. S. Serdyuk, Ie. Yu. Ovsii
We obtain asymptotic equalities for least upper bounds of deviations in the uniform metric of de la Vallée Poussin sums on the sets C^{q}_βH_ωof Poisson integrals of functions from…
On the best approximation of certain classes of periodic functions by trigonometric polynomials
A. S. Serdyuk, Ie. Yu. Ovsii
We obtain the estimates for the best approximation in the uniform metric of the classes of -periodic functions whose -derivatives have a given majorant of the modulu…