István Estélyi

activity

20142021

collaborators

3 papers

math.CO2021

On a representation of the automorphism group of a graph in a unimodular group

István Estelyi, Ján Karabáš, Alexander Mednykh +1

We investigate a representation of the automorphism group of a connected graph $X$ in the group of unimodular matrices $U_{β}$ of dimension $β$ , where $β$ is the Betti number of grap…

math.GR2015

Which Haar graphs are Cayley graphs?

István Estélyi, Tomaž Pisanski

For a finite group $G$ and subset $S$ of $G,$ the Haar graph $H (G, S)$ is a bipartite regular graph, defined as a regular $G$ -cover of a dipole with $∣ S ∣$ parallel arcs labelled by…

math.GR2014

On groups all of whose undirected Cayley graphs of bounded valency are integral

István Estélyi, István Kovács

A finite group $G$ is called Cayley integral if all undirected Cayley graphs over $G$ are integral, i.e., all eigenvalues of the graphs are integers. The Cayley integral groups hav…