Nikolay Yakovlevich Sonin

Nikolay Yakovlevich Sonin (February 22, 1849 - February 27, 1915) was a Russian mathematician.

He was born in Tula and 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 include Bernoulli polynomials 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. He died in St. Petersburg.