Robert Jajcay

collaborators

3 papers

math.GR2023

Cyclic complementary extensions and skew-morphisms

Kan Hu, Robert Jajcay

A cyclic complementary extension of a finite group $A$ is a finite group $G$ which contains $A$ and a cyclic subgroup $C$ such that $A \cap C = {1_{G}}$ and $G = A C$ . For any fixed gene…

math.CO2019

Bipartite Biregular Cages and Block Designs

Gabriela Araujo-Pardo, Alejandra Ramos-Rivera, Robert Jajcay

A bipartite biregular $(n, m; g)$ -graph $G$ is a bipartite graph of even girth $g$ having the degree set ${n, m}$ and satisfying the additional property that the vertices in the sam…

math.CO2018

Inverse monoids of partial graph automorphisms

Robert Jajcay, Tatiana Jajcayova, Nóra Szakács +1

A partial automorphism of a finite graph is an isomorphism between its vertex induced subgraphs. The set of all partial automorphisms of a given finite graph forms an inverse monoi…