Results 11 to 20 of about 166,067,780 (284)
Analytic approximation of matrix functions in $L^p$ [PDF]
Journal of Approximation Theory, 2008 We consider the problem of approximation of matrix functions of class $L^p$ on the unit circle by matrix functions analytic in the unit disk in the norm of $L^p$, $2\le ...
Laurent Baratchart +2 more
openaire +6 more sources
On Joint Approximation of Analytic Functions by Beurling Zeta-Functions
MathematicsFor j=1,…,r, let Pj be a system of generalized prime numbers, NPj the corresponding system of generalized integers, and ζPj(s), s=σ+it, the Beurling zeta-function. In the paper, we consider simultaneous approximation of a collection of analytic functions
Andrius Geštautas +2 more
doaj +2 more sources
Banach Spaces of Analytic Vector-valued Functions [PDF]
, 2007 The main theme of the thesis is the study of continuity and approximation problems, involving matrix-valued and vector-valued Hardy spaces on the unit disc ID and its boundary T in the complex plane.
Barclay, Steven John
core +7 more sources
Joint discrete approximation of analytic functions by Hurwitz zeta-functions
Mathematical Modelling and Analysis, 2022 Let H(D) be the space of analytic functions on the strip . In this paper, it is proved that there exists a closed non-empty set such that every collection of the functions is approximated by discrete shifts , of Hurwitz zeta-functions with arbitrary ...
Aidas Balčiūnas +4 more
doaj +1 more source
Approximation of Analytic Functions by Shifts of Certain Compositions
Mathematics, 2021 In the paper, we obtain universality theorems for compositions of some classes of operators in multidimensional space of analytic functions with a collection of periodic zeta-functions.
Darius Šiaučiūnas +2 more
doaj +1 more source
Joint universality of periodic zeta-functions with multiplicative coefficients. II
Nonlinear Analysis, 2021 In the paper, a joint discrete universality theorem for periodic zeta-functions with multiplicative coefficients on the approximation of analytic functions by shifts involving the sequence f kg of imaginary parts of nontrivial zeros of the Riemann zeta ...
Antanas Laurinčikas +2 more
doaj +1 more source
Some New Results on Bicomplex Bernstein Polynomials
Mathematics, 2021 The aim of this work is to consider bicomplex Bernstein polynomials attached to analytic functions on a compact C2-disk and to present some approximation properties extending known approximation results for the complex Bernstein polynomials. Furthermore,
Carlo Cattani +3 more
doaj +1 more source
Super-optimal approximation by meromorphic functions. [PDF]
, 1996 Let G be a matrix function of type m × n and suppose that G is expressible as the sum of an H∞ function and a continuous function on the unit circle. Suppose also that the (k – 1)th singular value of the Hankel operator with symbol G is greater than the ...
Young, N. J., Peller, V. V.
core +4 more sources
Approximation of analytic functions of exponential derived and integral bases in Fréchet spaces [PDF]
Assiut University Journal of Multidisciplinary Scientific Research, 2022 The purpose of this paper is to establish some theorems on the representation of analytic functions by exponential derived bases (EDBs) and exponential integral bases (EIBs) in Fréchet spaces.
Gamal Hassan, Amira Atta
doaj +1 more source
Joint discrete approximation of a pair of analytic functions by periodic zeta-functions
Mathematical Modelling and Analysis, 2020 In the paper, the problem of simultaneous approximation of a pair of analytic functions by a pair of discrete shifts of the periodic and periodic Hurwitz zeta-function is considered. The above shifts are defined by using the sequence of imaginary parts of
Aidas Balčiūnas +5 more
doaj +1 more source