Info: The AGDM seminar is a joint seminar of the University of Vienna and TU Wien. In winter semesters, we meet on Tuesdays from 15:00 to 16:30 at the University of Vienna. In summer semesters, we meet on Tuesdays from 15:15 to 16:45 at TU Wien.
Since 2025, we use a mailing-list to advertise the seminar. You can register here.
Place: University of Vienna, Oskar-Morgenstern-Platz 1, BZ 09 (first room on the right on the 9th floor)
Time:Tuesday, 15:00-16:30
| Date: | Tuesday 14.10.2025 |
| Title: | Two Topics, Four Lessons |
| Speaker: | Christian Krattenthaler (University of Vienna) |
| Abstract: | I will discuss two - unrelated - topics: (1) enumeration of two-rowed set-valued standard tableaux; (2) cyclic sieving for rooted plane trees. Obviously, I will explain what these topics are about. Maybe more important than the results are the lessons one can learn from the treatement of these problems: (1) enumeration problems for Motzkin paths are solved by the use of generating functions; (2) extraction of coefficients from power series involving implicitly defined functions is solved by the - appropriate! - application of Lagrange inversion; (3) how to prove integrality of factorial expressions and polynomiality of q-factorial expressions; (4) how to prove non-negativity of coefficients in such expressions. The second topic is joint with Mireille Bousquet-Mélou. |
Maintaining a respectful environment is essential to fostering meaningful dialogue and intellectual growth. Participants are expected to refrain from any form of disrespectful or inappropriate behaviour, including offensive comments, harassment, or disruptive conduct. Questions and contributions should be constructive, relevant to the topic, and posed in a professional manner that encourages healthy academic exchange. Harassment of any kind—including verbal, moral or physical—will not be tolerated, and all attendees are urged to uphold these principles to ensure a safe and welcoming atmosphere for everyone.
| 21.10.2025 | Sergio Fernandez de Soto Guerrero | MathMagic: A positroidal action over a deck of cards |
| 28.10.2025 | Shane Chern |
| 07.10.2025 | Matija Bucic (University of Vienna) | Equiangular lines via improved eigenvalue multiplicity |