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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">mathematics</journal-id><journal-title-group><journal-title xml:lang="ru">Вестник российских университетов. Математика</journal-title><trans-title-group xml:lang="en"><trans-title>Russian Universities Reports. Mathematics</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2686-9667</issn><issn pub-type="epub">2782-3342</issn><publisher><publisher-name>Тамбовский государственный университет имени Г.Р. Державина</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.20310/2686-9667-2026-31-154-128-141</article-id><article-id custom-type="elpub" pub-id-type="custom">mathematics-364</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>НАУЧНЫЕ СТАТЬИ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>ORIGINAL ARTICLES</subject></subj-group></article-categories><title-group><article-title>О спектральной задаче для связанной системы обыкновенных дифференциальных уравнений второго порядка с нелокальными взвешенными интегральными краевыми условиями</article-title><trans-title-group xml:lang="en"><trans-title>On a spectral problem for a coupled system of second-order ordinary differential equations with nonlocal weighted integral boundary conditions</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0009-0002-5765-7014</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Зекри</surname><given-names>Абделькрим</given-names></name><name name-style="western" xml:lang="en"><surname>Zekri</surname><given-names>Abdelkrim</given-names></name></name-alternatives><bio xml:lang="ru"><p>Зекри Абделькрим, доктор философии по математике, доцент  </p><p>13000, г. Тлемсен, ул. Барка Ахмед Буханнак Имама, 01</p></bio><bio xml:lang="en"><p>Abdelkrim Zekri, PhD in Mathematics, Associate Professor   </p><p>01 Rue Barka Ahmed Bouhannak, Imama, Tlemcen 13000</p></bio><email xlink:type="simple">zekri6080@gmail.com</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Высшая школа менеджмента Тлемсена</institution><country>Алжир</country></aff><aff xml:lang="en"><institution>Higher School of Management-Tlemcen</institution><country>Algeria</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2026</year></pub-date><pub-date pub-type="epub"><day>06</day><month>07</month><year>2026</year></pub-date><volume>31</volume><issue>154</issue><fpage>128</fpage><lpage>141</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Зекри А., 2026</copyright-statement><copyright-year>2026</copyright-year><copyright-holder xml:lang="ru">Зекри А.</copyright-holder><copyright-holder xml:lang="en">Zekri A.</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://mathematics.elpub.ru/jour/article/view/364">https://mathematics.elpub.ru/jour/article/view/364</self-uri><abstract><p>В данной работе исследуется спектральная задача для системы обыкновенных дифференциальных уравнений второго порядка с комплексным спектральным параметром при взвешенных интегральных краевых условиях, содержащих первые производные неизвестных функций. Для достаточно больших значений спектрального параметра получены априорные оценки решений системы и установлена фредгольмова разрешимость соответствующего оператора. Полученные результаты обобщают известные спектральные свойства и свойства разрешимости обыкновенных дифференциальных операторов с нелокальными интегральными условиями на случай связанных систем.</p></abstract><trans-abstract xml:lang="en"><p>In this work, we investigate a spectral problem for a system of second-order ordinary differential equations with a complex spectral parameter subject to weighted integral boundary conditions involving the first derivatives of the unknown functions. For sufficiently large values of the spectral parameter, we derive a priori estimates for solutions of the system and establish the Fredholm solvability of the corresponding operator. The obtained results extend known spectral and solvability properties for ordinary differential operators with nonlocal integral conditions to coupled systems.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>системы обыкновенных дифференциальных уравнений</kwd><kwd>интегральные краевые условия</kwd><kwd>фредгольмовы операторы</kwd><kwd>априорные оценки</kwd></kwd-group><kwd-group xml:lang="en"><kwd>systems of ordinary differential equations</kwd><kwd>integral boundary conditions</kwd><kwd>Fredholm operators</kwd><kwd>a priori estimates</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. L. Skubachevsky, “Nonclassical boundary-value problems. I”, Journal of Mathematical Sciences, 155:2 (2008), 199–334.</mixed-citation><mixed-citation xml:lang="en">A. L. Skubachevsky, “Nonclassical boundary-value problems. 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