Sidorov Sergei Petrovich Russia Saratov State University 1, Saratov State University, Russia, 410012, Saratov, Astrahanskaya st., 83 SidorovSP@info.sgu.ru Author's articles Simultaneous Approximation of Polynomial Functions and Its Derivatives by Feedforward Artificial Neural Networks with One Hidden Layer N. S. Differential evolution algorithm for solving the portfolio optimization problem Heuristic algorithm for the cardinality constrained portfolio optimization problem Shape-Preserving Linear n-width of Unit Balls in C[0, 1] 18th International Saratov Winter School “Contemporary Problems of Function Theory and Their Applications” In Memory of Alexandr Yu. Vasiliev The Error of Approximation of Differentiable Functions of Several Variables by Means of Interpolatory Shape-Preserving Operators ХРОНИКА НАУЧНОЙ ЖИЗНИ Empirical Analysis of Algorithms for Solving the Index Tracking Problem 19th International Saratov Winter School “Contemporary Problems of Function Theory and Their Applications“