4 papers
Regular, and (bi-)rotary Hall Cayley maps
Wendi Di, Zheng Guo, Cai Heng Li
A classification is given of regular, rotary, and birotary Cayley maps of which the vertex number is coprime to the valency. The classification is involved in constructions of new…
A classification of rotary embeddings of multicycles
Zhaochen Ding, Zheng Guo, Luyi Liu
We classify rotary (orientably-regular) maps whose underlying graphs are multicycles. For the multicycle of length and edge-multiplicity , we determine…
Hall Skew-morphisms and Hall Cayley maps of finite groups
Wendi Di, Zheng Guo, Cai Heng Li
A characterization is given of finite groups that have skew-morphisms of order coprime to the order , and their skew-morphisms. A complete classification is then given of…
The exceptional Hall numbers
Zheng Guo, Yong Hu, Cai Heng Li
A positive integer is called a Hall number if any finite group of order precisely divisible by has a Hall subgroup of order . We prove that, except for the obvious examp…