On the rate of convergence of some orthogonal polynomial expansions.
On the rate of pointwise convergence of Szász-Mirakyan operators
On the rate of strong summability by matrix means in the generalized Hölder metric.
On the rate of summability by matrix means in the generalized Hölder metric
We will generalize and improve the results of T. Singh [Publ. Math. Debrecen 40 (1992), 261-271] obtaining the L. Leindler type estimates from [Acta Math. Hungar. 104 (2004), 105-113].
On the rational Tschebyscheff operator.
On the Renorming of a Vector Space Endowed with Two Norms and the Simultaneous Best Approximation Problem.
On the Sets of Type VV++
On the sharpness of an approximation criterion of smoothness for functions on a segment
On the Sharpness of Non-Optimal Approximation for Semigroup Operators.
On the Sharpness of Theorems Concerning Zero-Free Regions for Certain Sequences of Polynomials.
On the size of approximately convex sets in normed spaces
Let X be a normed space. A set A ⊆ X is approximately convexif d(ta+(1-t)b,A)≤1 for all a,b ∈ A and t ∈ [0,1]. We prove that every n-dimensional normed space contains approximately convex sets A with and , where ℋ denotes the Hausdorff distance. These estimates are reasonably sharp. For every D>0, we construct worst possible approximately convex sets in C[0,1] such that ℋ(A,Co(A))=(A)=D. Several results pertaining to the Hyers-Ulam stability theorem are also proved.
On the strong summability and approximation of Fourier series
On the successive remainders of the exponential series.
On the theorem of Géza Grünwald and Józef Marcinkiewicz
This survey is a tribute to Géza Grünwald and Józef Marcinkiewicz dealing with the so called Grünwald-Marcinkiewicz Theorem.
On the total positivity of the truncated power kernel
On the trapezoid quadrature formula and applications
On the two dimensional spline interpolation of Hermite-type.
On the Uniform Approximation to Continuous Functions by Linear Aggregates of Translations.
On the uniform continuity of metric projection
On the uniform convergence and L¹-convergence of double Walsh-Fourier series
In 1970 C. W. Onneweer formulated a sufficient condition for a periodic W-continuous function to have a Walsh-Fourier series which converges uniformly to the function. In this paper we extend his results from single to double Walsh-Fourier series in a more general setting. We study the convergence of rectangular partial sums in -norm for some 1 ≤ p ≤ ∞ over the unit square [0,1) × [0,1). In case p = ∞, by we mean , the collection of uniformly W-continuous functions f(x, y), endowed with the...