На 5 ноември 2021 г. (петък) от 13:00 часа ще се проведе дистанционно заседание на семинара по „Алгебра и логика”.
Доклад на тема
Permutation groups and permutation patterns
ще изнесе Erkko Lehtonen (Universidade Nova de Lisboa, Portugal).
Абстракт. We approach permutations from two different points of view: the algebraic one of permutation groups and the combinatorial one of permutation patterns. While these two well-established notions do not seem to have much in common, there is a perhaps surprising connection that will be explained in this talk. Namely, the class of permutations avoiding the complement of a permutation group is comprised of levels that are permutation groups.
With the help of invariant relations, we describe the permutation groups that arise in this way from pattern avoidance. Furthermore, we propose refinements to the work by Atkinson and Beals on permutation classes in which all levels are groups.
This talk is partly based on joint work with Reinhard Pöschel (Technische Universität Dresden).
Семинарът ще се проведе посредством платформата Zoom и всеки желаещ може да се присъедини като последва линка:
https://us02web.zoom.us/j/85137375021?pwd=RE5QczdFTE1xL1R6MnI2b1lkcGczQT09
Topic: Онлайн семинар на секция “Алгебра и логика”
Time: Nov 05, 2021 01:00 PM Sofia
Meeting ID: 851 3737 5021
Passcode: 035647
От секция „Алгебра и логика” на ИМИ – БАН
http://www.math.bas.bg/algebra/seminarAiL/
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