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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">vestifm</journal-id><journal-title-group><journal-title xml:lang="ru">Известия Национальной академии наук Беларуси. Серия физико-математических наук</journal-title><trans-title-group xml:lang="en"><trans-title>Proceedings of the National Academy of Sciences of Belarus. Physics and Mathematics Series</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">1561-2430</issn><issn pub-type="epub">2524-2415</issn><publisher><publisher-name>The Republican Unitary Enterprise Publishing House "Belaruskaya Navuka"</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.29235/1561-2430-2026-62-1-7-14</article-id><article-id custom-type="elpub" pub-id-type="custom">vestifm-871</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>МАТЕМАТИКА</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>MATHEMATICS</subject></subj-group></article-categories><title-group><article-title>О существовании Hτ σ -критических формаций конечных групп</article-title><trans-title-group xml:lang="en"><trans-title>On the existence of H 𝜏σ -critical formations of finite groups</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>Скрундь</surname><given-names>В. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Skrundz</surname><given-names>V. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Скрундь Валентина Викторовна – аспирант кафедры высшей алгебры и защиты информации</p><p>пр. Независимости, 4, 220030, Минск</p></bio><bio xml:lang="en"><p>Valentina V. Skrundz – Postgraduate Student of the Department of Higher Algebra and Information Security</p><p>Nezavisimosti Ave., 4, 220030, Minsk</p></bio><email xlink:type="simple">vallik@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-6896-7208</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Сафонова</surname><given-names>И. Н.</given-names></name><name name-style="western" xml:lang="en"><surname>Safonova</surname><given-names>I. N.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Сафонова Инна Николаевна – доктор физико-математических наук, доцент, профессор кафедры высшей алгебры и защиты информации</p><p>пр. Независимости, 4, 220030, Минск</p></bio><bio xml:lang="en"><p>Inna N. Safonova – Dr. Sc. (Physics and Mathematics), Associate Professor, Professor of the Department of Higher Algebra and Information Security</p><p>Nezavisimosti Ave., 4, 220030, Minsk</p></bio><email xlink:type="simple">safonova@bsu.by</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Белорусский государственный университет</institution><country>Беларусь</country></aff><aff xml:lang="en"><institution>Belarusian State University</institution><country>Belarus</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2026</year></pub-date><pub-date pub-type="epub"><day>31</day><month>03</month><year>2026</year></pub-date><volume>62</volume><issue>1</issue><fpage>7</fpage><lpage>14</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Скрундь В.В., Сафонова И.Н., 2026</copyright-statement><copyright-year>2026</copyright-year><copyright-holder xml:lang="ru">Скрундь В.В., Сафонова И.Н.</copyright-holder><copyright-holder xml:lang="en">Skrundz V.V., Safonova I.N.</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://vestifm.belnauka.by/jour/article/view/871">https://vestifm.belnauka.by/jour/article/view/871</self-uri><abstract><p>Изучены 𝜏-замкнутые σ-локальные формации конечных групп, где σ – некоторое разбиение множества всех простых чисел, 𝜏 – произвольный подгрупповой функтор. Исследован вопрос существования  H𝜏σ -критических формаций, т. е. таких 𝜏-замкнутых σ-локальных формаций L H ⊆ , у которых все собственные 𝜏-замкнутые σ-локальные подформации содержатся в классе групп H. Доказано, что если H – σ-локальная формация классического типа, то у всякой 𝜏-замкнутой σ-локальной формации F  ⊆ H существует по меньшей мере одна  H 𝜏σ -критическая подформация.</p></abstract><trans-abstract xml:lang="en"><p>The 𝜏 -closed σ-local formations of finite groups are studied, where σ is some partition of the set of all primes, 𝜏  is an arbitrary subgroup functor. The question of the existence of 𝜏  Hσ -critical formations is investigated, i. e., such 𝜏 -closed σ-local formations L H ⊆ for which all proper 𝜏 -closed σ-local subformations are contained in the class of groups H. It is proved that if H is a σ-local formation of classical type, then every 𝜏 -closed σ-local formation F H ⊆ has at least one  H𝜏 σ - critical subformation.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>конечная группа</kwd><kwd>подгрупповой функтор</kwd><kwd>τ-замкнутая формация</kwd><kwd>формационная σ-функция</kwd><kwd>σ-локальная формация</kwd><kwd>критическая σ-локальная формация</kwd><kwd>формация классического типа</kwd></kwd-group><kwd-group xml:lang="en"><kwd>finite group</kwd><kwd>subgroup functor</kwd><kwd>τ-closed formation</kwd><kwd>formation σ-function</kwd><kwd>σ-local formation</kwd><kwd>critical σ-local formation</kwd><kwd>formation of classical type</kwd></kwd-group><funding-group><funding-statement xml:lang="ru">Исследования выполнены в рамках задания Государственной программы научных исследований «Конвергенция-2025» при финансовой поддержке Министерства образования Республики Беларусь (проект 20211328).</funding-statement><funding-statement xml:lang="en">The research was carried out in the framework of the State Program of Scientific Research “Convergence – 2025” with financial support of the Ministry of Education of the Republic of Belarus (project 20211328).</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">Голубев, В. 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