A note on maximum independent sets and minimum clique partitions in unit disk graphs and penny graphs: complexity and approximation
A is the intersection graph of a family of unit disks in the plane. If the disks do not overlap, it is also a or . It is known that finding a maximum independent set in a unit disk graph is a NP-hard problem. In this work we extend this result to penny graphs. Furthermore, we prove that finding a minimum clique partition in a penny graph is also NP-hard, and present two linear-time approximation algorithms for the computation of clique partitions: a -approximation algorithm for unit disk graphs...