Vladimir Igorevich Parusnikov

A. I. Aptekarev ; A. B. Batkhin ; A. D. Bruno

Čebyševskij sbornik, Tome 17 (2016) no. 1, pp. 286-298.

Résumé

Vladimir Igorevich Parusnikov died on August 22, 2015 after a long and serious illness. He was born in Moscow on January 21, 1957. Vladimir Igorevich graduated from the Department of Mechanics and Mathematics of the Lomonosov Moscow State University, finished his postgraduate studies in 1982 and he defended his thesis in 1983 in there. At the Keldysh Institute of Applied Mathematics he worked since 1982 as a junior researcher, and since 1996 — as a senior researcher. He has published more than 45 scientific papers on functional and numerical continued fractions and their generalizations. V. I. Parusnikov was kind, honest, responsible man and a talented mathematician. His passing is a great loss for the KIAM and for science in general. He was buried at Khovanskoye cemetery in Moscow. We provide a survey of his mathematical work. First, he studied the generalized functional continued fractions and got rather strong results. The last twenty years he, together with A. D. Bruno, was looking for a multi-dimensional generalization of the continued fraction giving the best Diophantine approximations and the periods in the algebraic case. Such a generalization was finally found. The first Section of the paper was written by A. I. Aptekarev, the second Section was written by A. D. Bruno, the list of scientific publications of V. I. Parusnikov was prepared by A. B. Batkhin. Bibliography: 71 titles.

Détail

Keywords: rational approximation, continued fraction, multidimensional generalization of continued fraction.

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