Fakulta matematiky, fyziky
a informatiky
Univerzita Komenského v Bratislave

# Algebraic Graph Theory International Webinar (18.4.2023)

## v utorok 18.4.2023 o 19:00 hod.

17. 04. 2023 11.33 hod.

The organizers of the Algebraic Graph Theory International Webinar would like to invite you to join us and other colleagues on April 18, 2023, at 7pm Central European Summer Time (= 5pm UTC, please note that we switched to summer time), for the next presentation delivered by Stefko Miklavic.

The title: (Closed) distance magic circulants

Abstract:
Let $\Gamma$ be a graph with vertex set $V$, and let $n=|V|$. A distance magic labelling of $\Gamma$ is a bijection $\ell : V \mapsto \{1,2, \ldots, n\}$ for which there exists a positive integer $r$ such that $\sum_{y \in \Gamma(x)} \ell(y) = r$ for all vertices $y \in V$, where $\Gamma(x)$ is the neighbourhood of $x$. Similarly, a closed distance magic labelling of $\Gamma$ is a bijection $\ell : V \mapsto \{1,2, \ldots, n\}$ for which there exists a positive integer $r$ such that $\sum_{y \in \Gamma[x]} \ell(y) = r$ for all vertices $y \in V$, where $\Gamma[x]$ is the closed neighbourhood of $x$. A graph is said to be (closed) distance magic if it admits a (closed) distance magic labelling. In this talk I will discuss (closed) distance magic circulants. The key ingredient of this research are eigenvalues and eigenvectors of circulant graphs, which could be computed using irreducible characters of cyclic groups.

The Zoom link for this semester is:

https://cuaieed-unam.zoom.us/j/87193320713?pwd=cHpiWUtYWlUvWHZjdGZteSt1QmZ5UT09
Meeting ID: 871 9332 0713
Passcode: 653250

Further details may be found at http://euler.doa.fmph.uniba.sk/AGTIW.html

where you can also find the slides and the recordings of our previous presentations. Also, if you wish to advertise an AGT friendly conference on this page, please send us the link.

Hoping to see you at the webinar, and wishing you all the best.