Mobile Sensor Nodes (MSNs) are featured with mobility along with other sensor functions. They are useful in hazardous and disastrous situations, where human intervention is not easy. The network life can be extended by conserving the energy of the nodes. Nodes deplete considerable amount of energy during their traversal. By making all the nodes travel approximately equal distance, their energy consumption can be made uniform. Another preferred requirement is to have holes free, 2-coverage sensing. Efficient Hexagonal 2-Coverage by Mobile Sensor Nodes uniquely balances the theoretical...