activity
20242026
most citedThe commuting graph and a graph associated with centralizers

1 citations · 1 across the 8 of their papers we have counts for

collaborators

9 papers

math.GR2026

Some answers regarding factorizations of finite groups

Ryan McCulloch

In this note we answer some questions of G. M. Bergman concerning factorizations of finite groups. Such questions originated when M. H. Hooshmand asked whether, given a finite grou…

math.GR2026

An answer regarding automorphisms of finite abelian groups

Ryan McCulloch

In this note we provide a negative answer to the question: ``Is it true that for every positive rational number there exists a finite abelian group such that $|\mathrm{Aut}…

math.GR2025

Covering by Centralizers

Mark L. Lewis, Ryan McCulloch

In this paper, we consider covers of finite groups by centralizers of elements. We show that the set of centralizers that are maximal under the partial ordering form a cover of the…

math.GR2025

A Möbius function on the centralizer lattice

William Cocke, Mark L. Lewis, Ryan McCulloch

We consider the Möbius function on the poset of element centers and obtain some new results regarding centralizers in a -group.

math.GR2025★ 1 cited

The commuting graph and a graph associated with centralizers

Mark L. Lewis, Ryan McCulloch

Let be a -group. We begin to consider the relationship between the structure of the commuting graph and . We also build a family of groups whose commuting graphs h…

math.CO2025

The Cycle Counts of Graphs

Ryan McCulloch, Brendan D. McKay, Alireza Salahshoori +1

We prove that an inseparable graph can have any positive number of cycles with the six exceptions 2, 4, 5, 8, 9, 16, and that an inseparable cubic graph has the additional exceptio…

math.GR2025

Finite groups with dense -subgroups

Ryan McCulloch, Marius Tărnăuceanu

A group is said to have dense -subgroups if each non-empty open interval of the subgroup lattice contains a subgroup in the Chermak--Delgado lattice ${\cal CD…

math.CO2025

Incidence Gain Graphs and Generalized Quadrangles

Ryan McCulloch

We demonstrate a construction method based on a gain function that is defined on the incidence graph of an incidence geometry. Restricting to when the incidence geometry is a linea…

math.CO2024

Locally resolvable BIBDs and generalized quadrangles with ovoids

Ryan McCulloch

In this note we establish a 1-to-1 correspondence between the class of generalized quadrangles with ovoids and the class of balanced incomplete block designs that posses a non-tria…