ON PLANARITY OF DIRECT PRODUCT OFMULTIPARTITE COMPLETE GRAPHS

摘要

The planarity of the direct product of two graphs has been widely studied in the past.Surprisingly, the missing part is the product with K2, which seems to be less predictible.In this piece of work, we characterize which subdivisions of multipartite complete graphs,have their direct product with K2 planar. This can be seen as a step towards the char-acterization of all such graphs.