The Approximation of Analytic Functions Using Shifts of the Lerch Zeta-Function in Short Intervals

In this paper, we obtain approximation theorems of classes of analytic functions by shifts <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>L</mi><mo>(</mo><mi>λ</mi>...

Full description

Saved in:
Bibliographic Details
Main Author: Antanas Laurinčikas
Format: Article
Language:English
Published: MDPI AG 2025-06-01
Series:Axioms
Subjects:
Online Access:https://www.mdpi.com/2075-1680/14/6/472
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850156303276572672
author Antanas Laurinčikas
author_facet Antanas Laurinčikas
author_sort Antanas Laurinčikas
collection DOAJ
description In this paper, we obtain approximation theorems of classes of analytic functions by shifts <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>L</mi><mo>(</mo><mi>λ</mi><mo>,</mo><mi>α</mi><mo>,</mo><mi>s</mi><mo>+</mo><mi>i</mi><mi>τ</mi><mo>)</mo></mrow></semantics></math></inline-formula> of the Lerch zeta-function for <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>τ</mi><mo>∈</mo><mo>[</mo><mi>T</mi><mo>,</mo><mi>T</mi><mo>+</mo><mi>H</mi><mo>]</mo></mrow></semantics></math></inline-formula> where <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>H</mi><mo>∈</mo><mo>[</mo><msup><mi>T</mi><mrow><mn>27</mn><mo>/</mo><mn>82</mn></mrow></msup><mo>,</mo><msup><mi>T</mi><mrow><mn>1</mn><mo>/</mo><mn>2</mn></mrow></msup><mo>]</mo></mrow></semantics></math></inline-formula>. The cases of all parameters, <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>λ</mi><mo>,</mo><mi>α</mi><mo>∈</mo><mo>(</mo><mn>0</mn><mo>,</mo><mn>1</mn><mo>]</mo></mrow></semantics></math></inline-formula>, are considered. If the set <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mo>{</mo><mi>log</mi><mrow><mo>(</mo><mi>m</mi><mo>+</mo><mi>α</mi><mo>)</mo></mrow><mo>:</mo><mi>m</mi><mo>∈</mo><msub><mi mathvariant="double-struck">N</mi><mn>0</mn></msub><mo>}</mo></mrow></semantics></math></inline-formula> is linearly independent over <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi mathvariant="double-struck">Q</mi></semantics></math></inline-formula>, then every analytic function in the strip <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mo>{</mo><mi>s</mi><mrow><mo>=</mo><mi>σ</mi><mo>+</mo><mi>i</mi><mi>t</mi></mrow><mo>∈</mo><mi mathvariant="double-struck">C</mi><mo>:</mo><mi>σ</mi><mo>∈</mo><mo>(</mo><mn>1</mn><mo>/</mo><mn>2</mn><mo>,</mo><mn>1</mn><mo>)</mo><mo>}</mo></mrow></semantics></math></inline-formula> is approximated by the above shifts.
format Article
id doaj-art-e0475ef026d24259838f2d36fd1e58e1
institution OA Journals
issn 2075-1680
language English
publishDate 2025-06-01
publisher MDPI AG
record_format Article
series Axioms
spelling doaj-art-e0475ef026d24259838f2d36fd1e58e12025-08-20T02:24:35ZengMDPI AGAxioms2075-16802025-06-0114647210.3390/axioms14060472The Approximation of Analytic Functions Using Shifts of the Lerch Zeta-Function in Short IntervalsAntanas Laurinčikas0Institute of Mathematics, Faculty of Mathematics and Informatics, Vilnius University, Naugarduko Str. 24, LT-03225 Vilnius, LithuaniaIn this paper, we obtain approximation theorems of classes of analytic functions by shifts <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>L</mi><mo>(</mo><mi>λ</mi><mo>,</mo><mi>α</mi><mo>,</mo><mi>s</mi><mo>+</mo><mi>i</mi><mi>τ</mi><mo>)</mo></mrow></semantics></math></inline-formula> of the Lerch zeta-function for <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>τ</mi><mo>∈</mo><mo>[</mo><mi>T</mi><mo>,</mo><mi>T</mi><mo>+</mo><mi>H</mi><mo>]</mo></mrow></semantics></math></inline-formula> where <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>H</mi><mo>∈</mo><mo>[</mo><msup><mi>T</mi><mrow><mn>27</mn><mo>/</mo><mn>82</mn></mrow></msup><mo>,</mo><msup><mi>T</mi><mrow><mn>1</mn><mo>/</mo><mn>2</mn></mrow></msup><mo>]</mo></mrow></semantics></math></inline-formula>. The cases of all parameters, <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>λ</mi><mo>,</mo><mi>α</mi><mo>∈</mo><mo>(</mo><mn>0</mn><mo>,</mo><mn>1</mn><mo>]</mo></mrow></semantics></math></inline-formula>, are considered. If the set <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mo>{</mo><mi>log</mi><mrow><mo>(</mo><mi>m</mi><mo>+</mo><mi>α</mi><mo>)</mo></mrow><mo>:</mo><mi>m</mi><mo>∈</mo><msub><mi mathvariant="double-struck">N</mi><mn>0</mn></msub><mo>}</mo></mrow></semantics></math></inline-formula> is linearly independent over <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi mathvariant="double-struck">Q</mi></semantics></math></inline-formula>, then every analytic function in the strip <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mo>{</mo><mi>s</mi><mrow><mo>=</mo><mi>σ</mi><mo>+</mo><mi>i</mi><mi>t</mi></mrow><mo>∈</mo><mi mathvariant="double-struck">C</mi><mo>:</mo><mi>σ</mi><mo>∈</mo><mo>(</mo><mn>1</mn><mo>/</mo><mn>2</mn><mo>,</mo><mn>1</mn><mo>)</mo><mo>}</mo></mrow></semantics></math></inline-formula> is approximated by the above shifts.https://www.mdpi.com/2075-1680/14/6/472Hurwitz zeta-functionLerch zeta-functionMergelyan theoremshort intervalsuniversalityweak convergence of probability measures
spellingShingle Antanas Laurinčikas
The Approximation of Analytic Functions Using Shifts of the Lerch Zeta-Function in Short Intervals
Axioms
Hurwitz zeta-function
Lerch zeta-function
Mergelyan theorem
short intervals
universality
weak convergence of probability measures
title The Approximation of Analytic Functions Using Shifts of the Lerch Zeta-Function in Short Intervals
title_full The Approximation of Analytic Functions Using Shifts of the Lerch Zeta-Function in Short Intervals
title_fullStr The Approximation of Analytic Functions Using Shifts of the Lerch Zeta-Function in Short Intervals
title_full_unstemmed The Approximation of Analytic Functions Using Shifts of the Lerch Zeta-Function in Short Intervals
title_short The Approximation of Analytic Functions Using Shifts of the Lerch Zeta-Function in Short Intervals
title_sort approximation of analytic functions using shifts of the lerch zeta function in short intervals
topic Hurwitz zeta-function
Lerch zeta-function
Mergelyan theorem
short intervals
universality
weak convergence of probability measures
url https://www.mdpi.com/2075-1680/14/6/472
work_keys_str_mv AT antanaslaurincikas theapproximationofanalyticfunctionsusingshiftsofthelerchzetafunctioninshortintervals
AT antanaslaurincikas approximationofanalyticfunctionsusingshiftsofthelerchzetafunctioninshortintervals