Joy Morris

activity

20112026

collaborators

Showing 2024Show all

3 papers · 1 filter

math.CO2024

Walecki tournaments with an arc that lies in a unique directed triangle

Joy Morris

A Walecki tournament is any tournament that can be formed by choosing an orientation for each of the Hamilton cycles in the Walecki decomposition of a complete graph on an odd numb…

math.CO2024

Groups with elements of order 8 do not have the DCI property

Ted Dobson, Joy Morris, Pablo Spiga

Let $k$ be odd, and $n$ an odd multiple of $3$ . We prove that $C_{k} ⋊ C_{8}$ and $(C_{n} \times C_{3}) ⋊ C_{8}$ do not have the Directed Cayley Isomorphism (DCI) property. When $…

math.CO2024

Haar graphical representations of finite groups and an application to poset representations

Joy Morris, Pablo Spiga

Let $R$ be a group and let $S$ be a subset of $R$ . The Haar graph $Haar (R, S)$ of $R$ with connection set $S$ is the graph having vertex set $R \times {- 1, 1}$ , where two di…