Results 1 to 10 of about 16,473 (262)

Joint universality of periodic zeta-functions with multiplicative coefficients

Nonlinear Analysis, 2020
The periodic zeta-function is defined by the ordinary Dirichlet series with periodic coefficients. In the paper, joint universality theorems on the approximation of a collection of analytic functions by nonlinear shifts of periodic zeta-functions with ...
Antanas Laurinčikas, Monika Tekorė
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A mixed joint universality theorem for zeta‐functions

Mathematical Modelling and Analysis, 2010
In the paper, a joint universality theorem for the Riemann zeta‐function and a collection of periodic Hurwitz zeta‐functions on approximation of analytic functions is obtained.
Jonas Genys, Renata Macaitienė, Santa Račkauskienė, Darius Šiaučiūnas   +3 more
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On a Dirichlet series connected to a periodic Hurwitz zeta-function with transcendental and rational parameter

Mathematical Modelling and Analysis, 2023
In the paper, we construct an absolutely convergent Dirichlet series which in the mean is close to the periodic Hurwitz zeta-function, and has the universality property on the approximation of a wide class of analytic functions.
Aidas Balčiūnas, Antanas Laurinčikas, Mindaugas Stoncelis   +2 more
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A Mixed Joint Universality Theorem for Zeta-Functions. II

Mathematical Modelling and Analysis, 2014
In the paper, a joint universality theorem on the approximation of analytic functions for zeta-function of a normalized Hecke eigen cusp form and a collection of periodic Hurwitz zeta-functions with algebraically independent parameters is obtained.
Vaida Pocevičienė, Darius Šiaučiūnas   +1 more
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Analytic approximations for special functions, applied to the modified Bessel functions I2(x) and I2/3(x)

Results in Physics, 2018
Simple analytic approximations valid for x⩾0 have been found for the modified Bessel functions I2(x) and I2/3(x), used amply in Electromagnetism and Mechanics applications.
Pablo Martin, Jorge Olivares, Fernando Maass, Elvis Valero   +3 more
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Approximation by Rational Functions in Variable Exponent Morrey–Smirnov Classes

Journal of Mathematics, 2022
In this work, the direct theorem of approximation theory in variable exponent Morrey–Smirnov classes of analytic functions, defined on a doubly connected domain of the complex plane bounded by two sufficiently smooth curves, is investigated.
Ahmed Kinj
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Analytic Approximation of Matrix Functions [PDF]

, 2003
We study in this chapter the problem of approximating an essentially bounded matrix function on 𝕋 by bounded analytic matrix functions in D. For such a matrix function Φ. ∈ L∞(𝕄 m,n ) its L∞ norm ||Φ||L∞ is, by definition, $$ {\left\| \Phi \right\|_{{L\infty }}} = ess\mathop{{\sup }}\limits_{{\zeta \in T}} {\left\| {\Phi \left( \zeta \right ...
openaire   +1 more source

Approximation by Ratios of Bounded Analytic Functions

Journal of Functional Analysis, 1998
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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Analysis of Higher-Order Bézier Curves for Approximation of the Static Magnetic Properties of NO Electrical Steels

Mathematics
Adequate mathematical description of magnetization curves is indispensable in engineering. The accuracy of the description has a significant impact on the design of electric machines and devices.
Ermin Rahmanović, Martin Petrun
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A Closed-Form Cubic–Logistic Approximation to the Normal Cumulative Distribution Function

Mathematics
Accurate evaluation of the standard normal cumulative distribution function is fundamental in many areas of mathematics, statistics, and applied computation, yet no closed-form expression in elementary functions exists.
Michael Arnold Frölich
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