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Nikolai Luzin

Nikolai Nikolayevich Luzin (also spelled Lusin; Russian: Никола́й Никола́евич Лу́зин, IPA: [nʲɪkɐˈlaj nʲɪkɐˈlaɪvʲɪtɕ ˈluzʲɪn] ; 9 December 1883 – 28 February 1950) was a Soviet and Russian mathematician known for his work in descriptive set theory and aspects of mathematical analysis with strong connections to point-set topology. He was the eponym of Luzitania, a loose group of young Moscow mathematicians of the first half of the 1920s. They adopted his set-theoretic orientation, and went on to apply it in other areas of mathematics.

Life edit

He started studying mathematics in 1901 at Moscow State University, where his advisor was Dmitri Egorov. He graduated in 1905.

Luzin underwent great personal turmoil in the years 1905 and 1906, when his materialistic worldview had collapsed and he found himself close to suicide. In 1906 he wrote to Pavel Florensky, a former fellow mathematics student who was now studying theology: You found me a mere child at the University, knowing nothing. I don't know how it happened, but I cannot be satisfied any more with analytic functions and Taylor series ... it happened about a year ago. ... To see the misery of people, to see the torment of life, to wend my way home from a mathematical meeting ... where, shivering in the cold, some women stand waiting in vain for dinner purchased with horror - this is an unbearable sight. It is unbearable, having seen this, to calmly study (in fact to enjoy) science. After that I could not study only mathematics, and I wanted to transfer to the medical school. The correspondence between the two men continued for many years and Luzin was greatly influenced by Florensky's religious treatise The Pillar and Foundation of Truth (1908).[1]

From 1910 to 1914 Luzin studied at Göttingen, where he was influenced by Edmund Landau. He then returned to Moscow and received his Ph.D. degree in 1915. During the Russian Civil War (1918–1920) Luzin left Moscow for the Polytechnical Institute Ivanovo-Voznesensk (now called Ivanovo State University of Chemistry and Technology). He returned to Moscow in 1920.

In the 1920s Luzin organized a famous research seminar at Moscow State University. His doctoral students included some of the most famous Soviet mathematicians: Pavel Alexandrov, Nina Bari, Aleksandr Khinchin, Andrey Kolmogorov, Aleksandr Kronrod, Mikhail Lavrentyev, Alexey Lyapunov, Lazar Lyusternik, Pyotr Novikov, Lev Schnirelmann and Pavel Urysohn.

On 5 January 1927 Luzin was elected as a corresponding member of the Academy of Sciences of the Soviet Union and became a full member of the Academy of Sciences of the Soviet Union first at the Department of Philosophy and then at the Department of Pure Mathematics (12 January 1929). In 1929 he was elected as a member of the Polish Academy of Sciences and Letters in Kraków.

Research work edit

Luzin's first significant result was a construction of an almost everywhere divergent trigonometric series with monotonic convergence to zero coefficients (1912). This example disproved the Pierre Fatou conjecture and was unexpected to most mathematicians at that time.

At approximately the same time, he proved what is now called Lusin's theorem in real analysis.

His Ph.D. thesis titled Integral and trigonometric series (1915) had a large impact on the subsequent development of the metric theory of functions. A set of problems formulated in this thesis for a long time attracted attention from mathematicians. For example, the first problem in the list, on the convergence of the Fourier series for a square-integrable function, came to be called Luzin's conjecture and was solved by Lennart Carleson[2] in 1966 (Carleson's theorem).

In the theory of boundary properties of analytic functions he proved an important result on the invariance of sets of boundary points under conformal mappings (1919).

Luzin was one of the founders of descriptive set theory.[3] Together with his student Mikhail Suslin, he developed the theory of analytic sets.

He also made contributions to complex analysis, the theory of differential equations, and numerical methods.[4]

Letter to Vygodsky edit

In a letter to M. Ya. Vygodsky dating from 1932, Luzin expresses sympathy with Vygodsky's infinitesimal approach to developing calculus. He mocks accusations of bourgeois decadence against Vygodsky's textbook, and relates his own youthful experience with what he felt were unnecessary formal complications of the traditional development of analysis. Typical is his youthful reaction to his teachers' insistence that the derivative is a limit: "They won't fool me: it's simply the ratio of infinitesimals, nothing else." A recent study notes that Luzin's letter contained remarkable anticipations of modern calculus with infinitesimals.[5]

Luzin affair of 1936 edit

On 21 November 1930, the declaration of the "initiative group" of the Moscow Mathematical Society which consisted of Luzin's former students Lazar Lyusternik and Lev Schnirelmann along with Alexander Gelfond and Lev Pontryagin claimed that “there appeared active counter-revolutionaries among mathematicians”.[6] Some of these mathematicians were pointed out, including the advisor of Luzin, Dmitri Egorov. In September 1930, Egorov was arrested on the basis of his religious beliefs. He then left the position of director of the Moscow Mathematical Society and was replaced by Ernst Kolman. As a result, Luzin left the Moscow Mathematical Society and Moscow State University. Egorov died on 10 September 1931, after a hunger strike initiated in prison. In 1931, Kolman brought the first complaint against Luzin.

In 1936 the Great Purge began. Millions of people were arrested or executed, including leading members of the intelligentsia. In July–August of that year, Luzin was criticized in Pravda in a series of anonymous articles whose authorship later was attributed to Kolman.[7] It was alleged that Luzin published “would-be scientific papers”, “felt no shame in declaring the discoveries of his students to be his own achievements”, and stood close to the ideology of the “black hundreds”, orthodoxy, and monarchy “fascist-type modernized but slightly.”[8] One of the complaints was that he published his major results in foreign journals.

The article triggered a special hearing on Luzin's case by the Commission of the Academy of Sciences of the Soviet Union, where the allegations were reviewed and formalized. At the hearing, Alexandrov, Lyusternik, Khinchin, Kolmogorov and some other students of Luzin accused him of plagiarism from Pyotr Novikov and Mikhail Suslin and various forms of misconduct, which included denying promotions to Kolmogorov and Khinchin. According to some researchers, Alexandrov and Kolmogorov had been involved in a homosexual relationship in the 1930s, a fact the police used to pressure them into testifying against their former teacher.[9] Sergei Sobolev, Gleb Krzhizhanovsky and Otto Schmidt incriminated Luzin with charges of disloyalty to Soviet power. The methods of political insinuations and slander had been used against the old Muscovite professorship already several years before the article in Pravda.

The hearings were completed in five sessions between July 7, 1936 and July 15, 1936, and people testifying, as well as the nature of accusations, changed from one session to another. In the initial session, the accusations were separated into accusations of scientific misconduct, which included plagiarism; accusations of professional misconduct, which mostly involved accusations of nepotism in promotions and reviews; and political accusations, which were the most serious. The initial review on July 7, which most prominently featured Alexandrov and Kolmogorov, concluded in a warning to Luzin regarding plagiarism while stressing the overall importance of his work, cleared him politically, yet recommended to relieve him of administrative duties.

However, this outcome did not seem to satisfy the instigators of the case, so that from the second hearing on, the nature of accusations shifted: now the primary focus was the fact that Luzin published his papers extensively in France rather than in Soviet journals, and his pre-Soviet sympathies were brought to the forefront.

The special hearing of the Commission of the Academy of Sciences of the Soviet Union endorsed all accusations of Luzin as an "enemy under the mask of a Soviet citizen."[8] Although the Commission convicted Luzin, he was neither expelled from the Academy nor arrested, but his department in the Steklov Institute was closed and he lost all his official positions. There has been some speculation about why his punishment was so much milder than that of most other people condemned at that time, but the reason for this does not seem to be known for certain. Historian of mathematics Adolph P. Yushkevich speculated that at the time, Stalin was more concerned with the forthcoming Moscow trials of Lev Kamenev, Grigory Zinoviev and others, whereas the eventual fate of Luzin was of a little interest to him.[10]

The 1936 decision of the Academy of Sciences was not canceled after Stalin's death.[8][11] The decision was finally reversed on January 17, 2012.[12][13]

Honors edit

In 1976, Martian crater Luzin was named in his honor.[14]

Bibliography edit

  • Luzin, N. N. (1931). Two letters by N. N. Luzin to M. Ya. Vygodskii. With an introduction by S. S. Demidov. Translated from the 1997 Russian original by Abe Shenitzer. The American Mathematical Monthly 107 (2000), no. 1, 64–82. JSTOR 2589382

See also edit

References edit

  1. ^ Ford, Charles E. (1998-08-01). "The Influence of P. A. Florensky on N. N. Luzin". Historia Mathematica. 25 (3): 332–339. doi:10.1006/hmat.1997.2182.
  2. ^ Carleson L. (1966). "On convergence and growth of partial sums of Fourier series". Acta Math. 116: 135–157. doi:10.1007/BF02392815.
  3. ^ Lusin Nicolas (1930). Leçons sur les Ensembles Analytiques et leurs Applications. With a preface by Henri Lebesgue and a note by Waclaw Sierpinski. Paris: Gauthier-Villars. p. 328.
  4. ^ For example, his work

    Лузин, Н. Н. (1931). "О методе академика А. Н. Крылова составления векового уравнения". Известия Академии наук СССР. VII серия. 7: 903–958. JFM 57.1455.01.

    is devoted to the Krylov subspace method
  5. ^ Katz, Mikhail; Tall, David (2011), Tension between Intuitive Infinitesimals and Formal Mathematical Analysis, Bharath Sriraman, Editor. Crossroads in the History of Mathematics and Mathematics Education. The Montana Mathematics Enthusiast Monographs in Mathematics Education 12, Information Age Publishing, Inc., Charlotte, NC, arXiv:1110.5747, Bibcode:2011arXiv1110.5747K
  6. ^ Bogolyubov A. N. and Rozhenko N.M. "The Experiment of 'Implanting' Dialectics into Mathematics from the End of the 1920s to the Beginning of the 1930s". Problems of Philosophy. No.9, 1991 (in Russian): 32–43.
  7. ^ Levin, A. E. (1990). "Anatomy of a public campaign: "Academician Luzin's case" in Soviet political history". Slavic Review. 49 (1). Slavic Review, Vol. 49, No. 1: 90–108. doi:10.2307/2500418. JSTOR 2500418. S2CID 155570928.
  8. ^ a b c Demidov, S. S.; Levshin, B. V., eds. (1999). Delo akademika Nikolaya Nikolayevicha Luzina [The case of Academician Nikolai Nikolayevich Luzin] (in Russian). St. Petersburg: Russkii Khristianskii Gumanitarnyi Institut. ISBN 5-88812-103-7. MR 1790419.
  9. ^ Graham, Loren R.; Kantor, Jean-Michel (2009). Naming infinity: a true story of religious mysticism and mathematical creativity. Harvard University Press. p. 185. ISBN 978-0-674-03293-4. The police soon learned of Kolmogorov and Alexandrov's homosexual bond, and they used that knowledge to obtain the behavior that they wished.
  10. ^ A.P. Yushkevich, The Lusin Affair (in Russian).
  11. ^ Demidov, Sergei S.; Ford, Charles E. (1996). N. N. Luzin and the affair of the "National Fascist Center". San Diego, CA: Academic Press. pp. 137–148. ISBN 5-88812-103-7. MR 1388788.
  12. ^ "Resolution No.8 of the Presidium of the Russian Academy of Sciences" (in Russian). RAS.
  13. ^ S.S. Kutateladze, An Epilog to the Luzin Case, Siberian Electronic Mathematical Reports, Vol. 10 (2013), A.1-6.
  14. ^ "Crater Luzin". Gazetteer of Planetary Nomenclature. USGS Astrogeology Research Program.

Further reading edit

  • The Case of Academician Nikolai Nikolayevich Luzin / eds. Sergei S. Demidov, Boris V. Levshin; trans. Roger Cooke. — American Mathematical Society, 2016. — 416 p. — (History of Mathematics, 43). — ISBN 9781470426088. — ISBN 1470426080.
  • Laugwitz, Detlef: Comments on the paper: "Two letters by N. N. Luzin to M. Ya. Vygodskiĭ". Amer. Math. Monthly 107 (2000), no. 1, 64–82. JSTOR 2589323

External links edit

nikolai, luzin, nikolai, nikolayevich, luzin, also, spelled, lusin, russian, Никола, Никола, евич, Лу, зин, nʲɪkɐˈlaj, nʲɪkɐˈlaɪvʲɪtɕ, ˈluzʲɪn, december, 1883, february, 1950, soviet, russian, mathematician, known, work, descriptive, theory, aspects, mathemati. Nikolai Nikolayevich Luzin also spelled Lusin Russian Nikola j Nikola evich Lu zin IPA nʲɪkɐˈlaj nʲɪkɐˈlaɪvʲɪtɕ ˈluzʲɪn 9 December 1883 28 February 1950 was a Soviet and Russian mathematician known for his work in descriptive set theory and aspects of mathematical analysis with strong connections to point set topology He was the eponym of Luzitania a loose group of young Moscow mathematicians of the first half of the 1920s They adopted his set theoretic orientation and went on to apply it in other areas of mathematics Nikolai LuzinBorn 1883 12 09 9 December 1883Irkutsk Russian EmpireDied28 February 1950 1950 02 28 aged 66 Moscow Soviet UnionNationalityRussianCitizenshipRussian Empire Soviet UnionAlma materMoscow State UniversityKnown forContributions to descriptive set theory mathematical analysis point set topology Luzin s theorem Lusin spaces Luzin sets Scientific careerFieldsMathematicianInstitutionsMoscow State University Steklov Mathematical Institute Polytechnical Institute Ivanovo VoznesenskThesisThe Integral and Trigonometric Series 1915 Doctoral advisorDmitri EgorovDoctoral studentsPavel AlexandrovNina BariAleksandr Khinchin Andrey Kolmogorov Alexander Kronrod Mikhail Lavrentyev Alexey Lyapunov Lazar Lyusternik Pyotr Novikov Lev Schnirelmann Pavel Urysohn Contents 1 Life 2 Research work 2 1 Letter to Vygodsky 3 Luzin affair of 1936 4 Honors 5 Bibliography 6 See also 7 References 8 Further reading 9 External linksLife editHe started studying mathematics in 1901 at Moscow State University where his advisor was Dmitri Egorov He graduated in 1905 Luzin underwent great personal turmoil in the years 1905 and 1906 when his materialistic worldview had collapsed and he found himself close to suicide In 1906 he wrote to Pavel Florensky a former fellow mathematics student who was now studying theology You found me a mere child at the University knowing nothing I don t know how it happened but I cannot be satisfied any more with analytic functions and Taylor series it happened about a year ago To see the misery of people to see the torment of life to wend my way home from a mathematical meeting where shivering in the cold some women stand waiting in vain for dinner purchased with horror this is an unbearable sight It is unbearable having seen this to calmly study in fact to enjoy science After that I could not study only mathematics and I wanted to transfer to the medical school The correspondence between the two men continued for many years and Luzin was greatly influenced by Florensky s religious treatise The Pillar and Foundation of Truth 1908 1 From 1910 to 1914 Luzin studied at Gottingen where he was influenced by Edmund Landau He then returned to Moscow and received his Ph D degree in 1915 During the Russian Civil War 1918 1920 Luzin left Moscow for the Polytechnical Institute Ivanovo Voznesensk now called Ivanovo State University of Chemistry and Technology He returned to Moscow in 1920 In the 1920s Luzin organized a famous research seminar at Moscow State University His doctoral students included some of the most famous Soviet mathematicians Pavel Alexandrov Nina Bari Aleksandr Khinchin Andrey Kolmogorov Aleksandr Kronrod Mikhail Lavrentyev Alexey Lyapunov Lazar Lyusternik Pyotr Novikov Lev Schnirelmann and Pavel Urysohn On 5 January 1927 Luzin was elected as a corresponding member of the Academy of Sciences of the Soviet Union and became a full member of the Academy of Sciences of the Soviet Union first at the Department of Philosophy and then at the Department of Pure Mathematics 12 January 1929 In 1929 he was elected as a member of the Polish Academy of Sciences and Letters in Krakow Research work editLuzin s first significant result was a construction of an almost everywhere divergent trigonometric series with monotonic convergence to zero coefficients 1912 This example disproved the Pierre Fatou conjecture and was unexpected to most mathematicians at that time At approximately the same time he proved what is now called Lusin s theorem in real analysis His Ph D thesis titled Integral and trigonometric series 1915 had a large impact on the subsequent development of the metric theory of functions A set of problems formulated in this thesis for a long time attracted attention from mathematicians For example the first problem in the list on the convergence of the Fourier series for a square integrable function came to be called Luzin s conjecture and was solved by Lennart Carleson 2 in 1966 Carleson s theorem In the theory of boundary properties of analytic functions he proved an important result on the invariance of sets of boundary points under conformal mappings 1919 Luzin was one of the founders of descriptive set theory 3 Together with his student Mikhail Suslin he developed the theory of analytic sets He also made contributions to complex analysis the theory of differential equations and numerical methods 4 Letter to Vygodsky edit In a letter to M Ya Vygodsky dating from 1932 Luzin expresses sympathy with Vygodsky s infinitesimal approach to developing calculus He mocks accusations of bourgeois decadence against Vygodsky s textbook and relates his own youthful experience with what he felt were unnecessary formal complications of the traditional development of analysis Typical is his youthful reaction to his teachers insistence that the derivative is a limit They won t fool me it s simply the ratio of infinitesimals nothing else A recent study notes that Luzin s letter contained remarkable anticipations of modern calculus with infinitesimals 5 Luzin affair of 1936 editOn 21 November 1930 the declaration of the initiative group of the Moscow Mathematical Society which consisted of Luzin s former students Lazar Lyusternik and Lev Schnirelmann along with Alexander Gelfond and Lev Pontryagin claimed that there appeared active counter revolutionaries among mathematicians 6 Some of these mathematicians were pointed out including the advisor of Luzin Dmitri Egorov In September 1930 Egorov was arrested on the basis of his religious beliefs He then left the position of director of the Moscow Mathematical Society and was replaced by Ernst Kolman As a result Luzin left the Moscow Mathematical Society and Moscow State University Egorov died on 10 September 1931 after a hunger strike initiated in prison In 1931 Kolman brought the first complaint against Luzin In 1936 the Great Purge began Millions of people were arrested or executed including leading members of the intelligentsia In July August of that year Luzin was criticized in Pravda in a series of anonymous articles whose authorship later was attributed to Kolman 7 It was alleged that Luzin published would be scientific papers felt no shame in declaring the discoveries of his students to be his own achievements and stood close to the ideology of the black hundreds orthodoxy and monarchy fascist type modernized but slightly 8 One of the complaints was that he published his major results in foreign journals The article triggered a special hearing on Luzin s case by the Commission of the Academy of Sciences of the Soviet Union where the allegations were reviewed and formalized At the hearing Alexandrov Lyusternik Khinchin Kolmogorov and some other students of Luzin accused him of plagiarism from Pyotr Novikov and Mikhail Suslin and various forms of misconduct which included denying promotions to Kolmogorov and Khinchin According to some researchers Alexandrov and Kolmogorov had been involved in a homosexual relationship in the 1930s a fact the police used to pressure them into testifying against their former teacher 9 Sergei Sobolev Gleb Krzhizhanovsky and Otto Schmidt incriminated Luzin with charges of disloyalty to Soviet power The methods of political insinuations and slander had been used against the old Muscovite professorship already several years before the article in Pravda The hearings were completed in five sessions between July 7 1936 and July 15 1936 and people testifying as well as the nature of accusations changed from one session to another In the initial session the accusations were separated into accusations of scientific misconduct which included plagiarism accusations of professional misconduct which mostly involved accusations of nepotism in promotions and reviews and political accusations which were the most serious The initial review on July 7 which most prominently featured Alexandrov and Kolmogorov concluded in a warning to Luzin regarding plagiarism while stressing the overall importance of his work cleared him politically yet recommended to relieve him of administrative duties However this outcome did not seem to satisfy the instigators of the case so that from the second hearing on the nature of accusations shifted now the primary focus was the fact that Luzin published his papers extensively in France rather than in Soviet journals and his pre Soviet sympathies were brought to the forefront The special hearing of the Commission of the Academy of Sciences of the Soviet Union endorsed all accusations of Luzin as an enemy under the mask of a Soviet citizen 8 Although the Commission convicted Luzin he was neither expelled from the Academy nor arrested but his department in the Steklov Institute was closed and he lost all his official positions There has been some speculation about why his punishment was so much milder than that of most other people condemned at that time but the reason for this does not seem to be known for certain Historian of mathematics Adolph P Yushkevich speculated that at the time Stalin was more concerned with the forthcoming Moscow trials of Lev Kamenev Grigory Zinoviev and others whereas the eventual fate of Luzin was of a little interest to him 10 The 1936 decision of the Academy of Sciences was not canceled after Stalin s death 8 11 The decision was finally reversed on January 17 2012 12 13 Honors editIn 1976 Martian crater Luzin was named in his honor 14 Bibliography editLuzin N N 1931 Two letters by N N Luzin to M Ya Vygodskii With an introduction by S S Demidov Translated from the 1997 Russian original by Abe Shenitzer The American Mathematical Monthly 107 2000 no 1 64 82 JSTOR 2589382See also editDenjoy Luzin theorem Denjoy Luzin Saks theorem Lusin s theorem Luzin spaceReferences edit Ford Charles E 1998 08 01 The Influence of P A Florensky on N N Luzin Historia Mathematica 25 3 332 339 doi 10 1006 hmat 1997 2182 Carleson L 1966 On convergence and growth of partial sums of Fourier series Acta Math 116 135 157 doi 10 1007 BF02392815 Lusin Nicolas 1930 Lecons sur les Ensembles Analytiques et leurs Applications With a preface by Henri Lebesgue and a note by Waclaw Sierpinski Paris Gauthier Villars p 328 For example his work Luzin N N 1931 O metode akademika A N Krylova sostavleniya vekovogo uravneniya Izvestiya Akademii nauk SSSR VII seriya 7 903 958 JFM 57 1455 01 is devoted to the Krylov subspace method Katz Mikhail Tall David 2011 Tension between Intuitive Infinitesimals and Formal Mathematical Analysis Bharath Sriraman Editor Crossroads in the History of Mathematics and Mathematics Education The Montana Mathematics Enthusiast Monographs in Mathematics Education 12 Information Age Publishing Inc Charlotte NC arXiv 1110 5747 Bibcode 2011arXiv1110 5747K Bogolyubov A N and Rozhenko N M The Experiment of Implanting Dialectics into Mathematics from the End of the 1920s to the Beginning of the 1930s Problems of Philosophy No 9 1991 in Russian 32 43 Levin A E 1990 Anatomy of a public campaign Academician Luzin s case in Soviet political history Slavic Review 49 1 Slavic Review Vol 49 No 1 90 108 doi 10 2307 2500418 JSTOR 2500418 S2CID 155570928 a b c Demidov S S Levshin B V eds 1999 Delo akademika Nikolaya Nikolayevicha Luzina The case of Academician Nikolai Nikolayevich Luzin in Russian St Petersburg Russkii Khristianskii Gumanitarnyi Institut ISBN 5 88812 103 7 MR 1790419 Graham Loren R Kantor Jean Michel 2009 Naming infinity a true story of religious mysticism and mathematical creativity Harvard University Press p 185 ISBN 978 0 674 03293 4 The police soon learned of Kolmogorov and Alexandrov s homosexual bond and they used that knowledge to obtain the behavior that they wished A P Yushkevich The Lusin Affair in Russian Demidov Sergei S Ford Charles E 1996 N N Luzin and the affair of the National Fascist Center San Diego CA Academic Press pp 137 148 ISBN 5 88812 103 7 MR 1388788 Resolution No 8 of the Presidium of the Russian Academy of Sciences in Russian RAS S S Kutateladze An Epilog to the Luzin Case Siberian Electronic Mathematical Reports Vol 10 2013 A 1 6 Crater Luzin Gazetteer of Planetary Nomenclature USGS Astrogeology Research Program Further reading editThe Case of Academician Nikolai Nikolayevich Luzin eds Sergei S Demidov Boris V Levshin trans Roger Cooke American Mathematical Society 2016 416 p History of Mathematics 43 ISBN 9781470426088 ISBN 1470426080 Laugwitz Detlef Comments on the paper Two letters by N N Luzin to M Ya Vygodskiĭ Amer Math Monthly 107 2000 no 1 64 82 JSTOR 2589323External links editO Connor John J Robertson Edmund F Nikolai Luzin MacTutor History of Mathematics Archive University of St Andrews O Connor John J Robertson Edmund F The 1936 Luzin affair MacTutor History of Mathematics Archive University of St Andrews Lorentz G G Mathematics and Politics in the Soviet Union from 1928 to 1953 Kutateladze S S The Tragedy of Mathematics in Russia Kutateladze S S Roots of Luzin s Case Retrieved from https en wikipedia org w index php title Nikolai Luzin amp oldid 1183926800, wikipedia, wiki, book, books, library,

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