REGULAR CORONOID SYSTEMS

A coronoid system H can be regarded as a hexagonal system that is allo wed to have 'holes' such that the perimeter of H and the perimeters of the holes are pairwise disjoint. H is said to be normal if it has no fixed bond, A normal coronoid system is called regular if it can be co nstructed from a smaller one that has already been recognized as regul ar by adding a hexagon in some special ways. In this paper a necessary and sufficient condition for a coronoid system to be regular is given .