Results 11 to 20 of about 16,473 (262)
Approximation of Analytic Functions by Kummer Functions [PDF]
Journal of Inequalities and Applications, 2010 We solve the inhomogeneous Kummer differential equation of the form xy′′+(β-x)y′-αy=∑m=0∞amxm and apply this result to the proof of a local Hyers-Ulam stability of the Kummer differential equation ...
Soon-Mo Jung
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Approximation of Analytic Functions by Chebyshev Functions [PDF]
Abstract and Applied Analysis, 2011 We solve the inhomogeneous Chebyshev's differential equation and apply this result for approximating analytic functions by the Chebyshev functions.
Soon-Mo Jung, Themistocles M. Rassias
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Approximation of Analytic Functions by Bessel's Functions of Fractional Order [PDF]
Abstract and Applied Analysis, 2011 We will solve the inhomogeneous Bessel's differential equation x2y″(x)+xy′(x)+(x2-ν2)y(x)=∑m=0∞amxm, where ν is a positive nonintegral number and apply this result for approximating analytic functions of a special type by ...
Soon-Mo Jung
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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
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Gram Points in the Universality of the Dirichlet Series with Periodic Coefficients
Mathematics, 2023 Let a={am:m∈N} be a periodic multiplicative sequence of complex numbers and L(s;a), s=σ+it a Dirichlet series with coefficients am. In the paper, we obtain a theorem on the approximation of non-vanishing analytic functions defined in the strip 1 ...
Darius Šiaučiūnas, Monika Tekorė
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Joint Approximation of Analytic Functions by Shifts of Lerch Zeta-Functions
Mathematics, 2023 In this paper, we consider the simultaneous approximation of tuples of analytic functions by tuples of shifts of Lerch zeta-functions with arbitrary parameters.
Antanas Laurinčikas +2 more
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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
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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
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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
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Superoptimal Analytic Approximations of Matrix Functions
Journal of Functional Analysis, 1994 The paper deals with the problem of approximation of a bounded matrix function \(G\) on the unit circle by functions \(Q\) bounded and analytic in the unit disk. In the case of continuous \(G\) it is stated that there exists a unique \(Q\) such that \(G- Q\) minimizes the singular values. The structure of the error \(G-Q\) and smoothness properties of \
Peller, V. V., Young, N. J.
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