3 papers
math.GR2024
On the number of generators of groups acting arc-transitively on graphs
Marco Barbieri, Pablo Spiga
Given a finite connected graph and a group acting transitively on the vertices of , we prove that the number of vertices of and the cardinality of are bounded ab…
math.GR2024
On the proportion of derangements and on suborbits in finite transitive groups
Marco Barbieri, Pablo Spiga
We find a lower bound on the proportion of derangements in a finite transitive group that depends on the minimal nontrivial subdegree. As a consequence, we prove that, if is a…
math.CO2023
Vertex-primitive digraphs with large fixity
Marco Barbieri, Primož Potočnik
The relative fixity of a digraph is defined as the ratio between the largest number of vertices fixed by a nontrivial automorphism of and the number of vertices of . We…