activity
20222024
most citedOn the number of fixed edges of automorphisms of vertex-transitive graphs of small valency

3 citations · 8 across the 6 of their papers we have counts for

collaborators

6 papers

math.GR2024★ 1 cited

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★ 1 cited

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…

math.CO2023★ 1 cited

On the order of semiregular automorphisms of cubic vertex-transitive graphs

Marco Barbieri, Valentina Grazian, Pablo Spiga

We prove that, if is a finite connected cubic vertex-transitive graph, then either there exists a semiregular automorphism of of order at least , or the number of vertic…

math.CO2022★ 3 cited

On the number of fixed edges of automorphisms of vertex-transitive graphs of small valency

Marco Barbieri, Valentina Grazian, Pablo Spiga

We prove that, if is a finite connected -valent vertex-transitive, or -valent vertex- and edge-transitive graph, then either is part of a well-understood family of gr…

math.CO2022★ 2 cited

On the Cayleyness of Praeger-Xu graphs

Marco Barbieri, Valentina Grazian, Pablo Spiga

We give a sufficient and necessary condition for a Praeger-Xu graph to be a Cayley graph.