Remembering Oleksandr Mykolayovych Sharkovsky

Professor Oleksandr M. Sharkovsky (December 7, 1936–November 21, 2022) was an honorary editorial board member of the International Journal of Bifurcation and Chaos. He left to the scientific world a famous Sharkovsky theorem established in his 1964 paper "Coexistence of Cycles of a Continuous Map of the Line into Itself," which laid the foundation of a new branch in the theory of dynamical systems — combinatorial dynamics. His contributions also include the Sharkovsky ordering, Sharkovsky space, Sharkovsky set, Sharkovsky stratification, and maximum period in the sense of Sharkovsky, among others. Professor Sharkovsky will be remembered forever.