Nikolay Yakovlevich Sonin

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Born: 22 Feb 1849 in Tula, Russia
Died: 27 Feb 1915 in Petrograd (now St Petersburg), Russia

Nikolay Sonin attended Moscow University studying mathematics and physics there from 1865 to 1869. He obtained a Master's Degree with a thesis submitted in 1871, then he taught at the University of Warsaw where he obtained a doctorate in 1874. He was appointed to a chair in the University of Warsaw in 1876. In 1894 Sonin moved to St Petersburg where he taught at the University for Women.

Sonin worked on special functions, in particular cylindrical functions. He also worked on the Euler- Maclaurin summation formula.

Other topics Sonin studied included Bernoulli polynomials (Jacob Bernoulli) and approximate computation of definite integrals, continuing Chebyshev's work on numerical integration.

Together with A A Markov, Sonin prepared a two volume edition of Chebyshev's works in French and Russian.