Key research themes
1. What are the conditions and constructions for group {1, −1, i, −i} cordial labeling on product and splitting graphs?
This research theme explores the notion of group {1, −1, i, −i} cordial labeling in the context of product graphs (such as Cartesian products, hypercubes, books, prisms) and splitting graphs derived from standard graph classes (paths, cycles, wheels, stars, fans, combs, ladders). The labeling assigns group elements to vertices and edge labels based on orders of elements, aiming for balance constraints in vertex and edge label distributions (vertex and edge counts differing by at most one). Understanding these constructions matters for extending graph labeling concepts and characterizing cordiality in product-related graph structures with algebraic constraints.
2. How do product cordial labeling and total product cordial labeling extend to cartesian and powers of standard graphs?
This theme investigates product cordial labelings, where vertex labels in {0,1} induce edge labels by multiplicative products modulo 2, and total product cordial labelings, which include combined vertex and edge label counts in balancing conditions. Research here characterizes these labelings for cartesian products of paths and cycles, generalized Petersen graphs, and powers of paths. Insight into these labelings is significant as they generalize cordial labelings and connect labeling combinatorics with graph product structures, enriching the catalog of graphs recognized as product cordial.
3. What extensions of friendly and solitary number concepts can be made in group theory to define and study friendly and solitary groups?
This research direction carries over classical notions from number theory — friendly numbers (sharing the same abundancy index) and solitary numbers (unique abundancy index) — to finite group theory by defining analogous abundancy measures based on sums of orders of normal subgroups relative to group order. Study of friendly and solitary groups types 1 and 2 aims to discover structural properties and club formations involving cyclic and non-cyclic groups, providing a new lens on group classification with potential applications in algebraic structures.