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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">cheb</journal-id><journal-title-group><journal-title xml:lang="ru">Чебышевский сборник</journal-title><trans-title-group xml:lang="en"><trans-title>Chebyshevskii Sbornik</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2226-8383</issn><publisher><publisher-name>Tula State Lev Tolstoy  Pedagogical University</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.22405/2226-8383-2022-23-3-245-248</article-id><article-id custom-type="elpub" pub-id-type="custom">cheb-1359</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>Краткие сообщения</subject></subj-group></article-categories><title-group><article-title>Уточнение оценки среднего угла в проблеме Фейеш Тота</article-title><trans-title-group xml:lang="en"><trans-title>Refinement of the mean angle estimation in the Feyesh Toth problem</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Горбачев</surname><given-names>Дмитрий Викторович</given-names></name><name name-style="western" xml:lang="en"><surname>Gorbachev</surname><given-names>Dmitry Viktorovich</given-names></name></name-alternatives><bio xml:lang="ru"><p>доктор физико-математических наук</p></bio><bio xml:lang="en"><p>doctor of physical and mathematical sciences</p></bio><email xlink:type="simple">dvgmail@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Лепетков</surname><given-names>Даниил Русламович</given-names></name><name name-style="western" xml:lang="en"><surname>Lepetkov</surname><given-names>Daniil Ruslamovich</given-names></name></name-alternatives><email xlink:type="simple">Shipsdays@gmail.com</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Тульский государственный университет</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Tula State University</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2022</year></pub-date><pub-date pub-type="epub"><day>31</day><month>12</month><year>2022</year></pub-date><volume>23</volume><issue>3</issue><fpage>245</fpage><lpage>248</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Горбачев Д.В., Лепетков Д.Р., 2022</copyright-statement><copyright-year>2022</copyright-year><copyright-holder xml:lang="ru">Горбачев Д.В., Лепетков Д.Р.</copyright-holder><copyright-holder xml:lang="en">Gorbachev D.V., Lepetkov D.R.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.chebsbornik.ru/jour/article/view/1359">https://www.chebsbornik.ru/jour/article/view/1359</self-uri><abstract><p>Рассматривается проблема Фейеш Тота о максимуме 𝐸* среднего значения суммы углов между прямыми в R3 с общим центром. Л. Фейеш Тот предположил, что𝐸* = 𝜋/3 = 1.047 . . .. Эта гипотеза до сих пор не доказана. D. Bilyk и R.W. Matzke доказали, что 𝐸*&lt;= 1.110 . . .. Мы уточняем эту оценку при помощи экстремальной задачи типа Дельсарта: 𝐸* &lt;=𝐴* &lt;= 1.08326. При помощи двойственной проблемы 𝐵* мы показываем, что решение задачи 𝐴* не позволяет доказать гипотезу Фейеш Тота, так как 1.05210 &lt; 𝐴*.</p></abstract><trans-abstract xml:lang="en"><p>The Fejes T´oth problem about the maximum 𝐸* of the mean value of the sum of angles between lines in R3 with a common center is considered. L. Fejes T´oth suggested that 𝐸* = 𝜋/3 = 1.047 . . .. This conjecture has not yet been proven. D. Bilyk and R.W. Matzke proved that 𝐸*&lt;= 1.110 . . .. We refine this estimate using an extremal problem of the Delsarte type: 𝐸* &lt;= 𝐴* &lt;= 1.08326. Using the dual problem 𝐵* we show that the solution of the 𝐴* problem does not allow us to prove the Fejes T´oth conjecture, since 1.05210 &lt; 𝐴*.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>гипотеза Фейеш Тота</kwd><kwd>единичная сфера</kwd><kwd>многочлен Лежандра</kwd><kwd>оценка линейного программирования</kwd><kwd>задача Дельсарта.</kwd></kwd-group><kwd-group xml:lang="en"><kwd>Fejes T´oth conjecture</kwd><kwd>unit sphere</kwd><kwd>Legendre polynomial</kwd><kwd>linear programming bound</kwd><kwd>Delsarte problem.</kwd></kwd-group><funding-group><funding-statement xml:lang="ru">Исследование выполнено за счет гранта Российского научного фонда № 18-11-00199, https://rscf.ru/project/18-11-00199/.</funding-statement><funding-statement xml:lang="en">This Research was performed by a grant of Russian Science Foundation (project 18-11-00199), https://rscf.ru/project/18-11-00199/.</funding-statement></funding-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Андреев Н.Н., Юдин В.А. 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