Чтобы присоединиться к семинару, за несколько минут до начала подключитесь к конференции Zoom по ссылке https://us02web.zoom.us/j/81220793393 или вручную, введя номер конференции 812 2079 3393 в приложении Zoom.Kleene iteration, or Kleene star, is one of the most intriguing algebraic operations appearing in theoretical computer science. Usually, the Kleene star is interpreted as the limit of n-th powers of an element. This is how it behaves in algebras of formal languages and in relational algebras. In the talk, we shall show some examples of structures with non-standard Kleene iteration, and apply them to proving some results for corresponding logical theories.