activity
20162020
collaborators

10 papers

math.CO2022

A new infinite family of star normal quotient graphs of twisted wreath type

Eda Kaja, Luke Morgan

We construct the first infinite families of locally arc transitive graphs with the property that the automorphism group has two orbits on vertices and is quasiprimitive on exactly…

math.GR2020

Vertex-transitive graphs with local action the symmetric group on ordered pairs

Luke Morgan

We consider a finite, connected and simple graph that admits a vertex-transitive group of automorphisms . Under the assumption that, for all , the local action $…

math.CO2019

The NNN-Property of Cyclic Groups

Michael Giudici, Luke Morgan, Yian Xu

A Cayley graph is said to be an NNN-graph if it is both normal and non-normal for isomorphic regular groups, and a group has the NNN-property if there exists an NNN-graph for it. I…

math.GR2019

Generalised shuffle groups

Carmen Amarra, Luke Morgan, Cheryl E. Praeger

The mathematics of shuffling a deck of cards with two "perfect shuffles" was brought into clarity by Diaconis, Graham and Kantor. Here we consider a generalisation of this pro…

math.GR2018

The distinguishing number of quasiprimitive and semiprimitive groups

Alice Devillers, Scott Harper, Luke Morgan

The distinguishing number of $G \leqslant \sym(Ω)$ is the smallest size of a partition of such that only the identity of fixes all the parts of the partition. Extending ear…

math.GR2018

Bounds for Finite Semiprimitive Permutation Groups: Order, Base Size, and Minimal Degree

Luke Morgan, Cheryl E. Praeger, Kyle Rosa

In this paper we study finite semiprimitive permutation groups, that is, groups in which each normal subgroup is transitive or semiregular. We give bounds on the order, base size,…