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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">mais</journal-id><journal-title-group><journal-title xml:lang="ru">Моделирование и анализ информационных систем</journal-title><trans-title-group xml:lang="en"><trans-title>Modeling and Analysis of Information Systems</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">1818-1015</issn><issn pub-type="epub">2313-5417</issn><publisher><publisher-name>Yaroslavl State University</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.18255/1818-1015-2025-2-100-109</article-id><article-id custom-type="elpub" pub-id-type="custom">mais-1935</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>Discrete Mathematics in Relation to Computer Science</subject></subj-group></article-categories><title-group><article-title>Об экстремальных элементах и мощности множества непрерывно дифференцируемых выпуклых продолжений булевой функции</article-title><trans-title-group xml:lang="en"><trans-title>On extremal elements and the cardinality of the set of continuously differentiable convex extensions of a Boolean function</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-5047-7710</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Баротов</surname><given-names>Достонжон Нумонжонович</given-names></name><name name-style="western" xml:lang="en"><surname>Barotov</surname><given-names>Dostonjon N.</given-names></name></name-alternatives><email xlink:type="simple">DNBarotov@fa.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/0000-0003-3729-6143</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Баротов</surname><given-names>Рузибой Нумонжонович</given-names></name><name name-style="western" xml:lang="en"><surname>Barotov</surname><given-names>Ruziboy N.</given-names></name></name-alternatives><email xlink:type="simple">DNBarotov@fa.ru</email><xref ref-type="aff" rid="aff-2"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Финансовый университет при Правительстве Российской Федерации</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Financial University under the Government of the Russian Federation</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>Худжандский государственный университет имени академика Б. Гафурова</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Khujand State University named after academician Bobojon Gafurov</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2025</year></pub-date><pub-date pub-type="epub"><day>28</day><month>06</month><year>2025</year></pub-date><volume>32</volume><issue>2</issue><fpage>100</fpage><lpage>109</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Баротов Д.Н., Баротов Р.Н., 2025</copyright-statement><copyright-year>2025</copyright-year><copyright-holder xml:lang="ru">Баротов Д.Н., Баротов Р.Н.</copyright-holder><copyright-holder xml:lang="en">Barotov D.N., Barotov R.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://www.mais-journal.ru/jour/article/view/1935">https://www.mais-journal.ru/jour/article/view/1935</self-uri><abstract><p>В данной статье изучается существование максимального и минимального элементов множества непрерывно дифференцируемых выпуклых продолжений на $[0,1]^n$ произвольной булевой функции $f_{B}(x_1,x_2,\ldots,x_n)$ и мощность множества непрерывно дифференцируемых выпуклых продолжений на $[0,1]^n$ булевой функции $f_{B}(x_1,x_2,\ldots,x_n)$. В результате исследования установлено, что мощность множества непрерывно дифференцируемых выпуклых продолжений на $[0,1]^n$ произвольной булевой функции $f_{B}(x_1,x_2,\ldots,x_n)$ равна континууму. Аргументировано, что для любой булевой функции $f_{B}(x_1,x_2,\ldots,x_n)$ среди её непрерывно дифференцируемых выпуклых продолжений на $[0,1]^n$ нет минимального элемента. Доказано, что для любой булевой функции $f_{B}(x_1,x_2,\ldots,x_n)$ множество её непрерывно дифференцируемых выпуклых продолжений на $[0,1]^n$ имеет максимальный элемент лишь тогда, когда количество существенных переменных данной булевой функции $f_{B}(x_1,x_2,\ldots,x_n)$ меньше 2.</p></abstract><trans-abstract xml:lang="en"><p>In this paper we study the existence of the maximal and minimal elements of the set of continuously differentiable convex extensions to $[0,1]^n$ of an arbitrary Boolean function $f_{B}(x_1,x_2,\ldots,x_n)$ and the cardinality of the set of continuously differentiable convex extensions to $[0,1]^n$ of the Boolean function $f_{B}(x_1,x_2,\ldots,x_n)$. As a result of the study, it was established that the cardinality of the set of continuously differentiable convex extensions to $[0,1]^n$ of an arbitrary Boolean function $f_{B}(x_1,x_2,\ldots,x_n)$ is equal to the continuum. It is argued that for any Boolean function $f_{B}(x_1,x_2,\ldots,x_n)$, there is no minimal element among its continuously differentiable convex extensions to $[0,1]^n$. It is proved that for any Boolean function $f_{B}(x_1,x_2,\ldots,x_n)$, the set of its continuously differentiable convex extensions to $[0,1]^n$ has a maximal element only if the number of essential variables of the given Boolean function $f_{B}(x_1,x_2,\ldots,x_n)$ is less than 2.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>непрерывно дифференцируемое выпуклое продолжение булевой функции</kwd><kwd>экстремальные элементы множества</kwd><kwd>мощность множества</kwd></kwd-group><kwd-group xml:lang="en"><kwd>continuously differentiable convex extension of a Boolean function</kwd><kwd>extremal elements of a set</kwd><kwd>cardinality of a set</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">A. H. 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