Hexagonal systems. A chemistry-motivated excursion to combinatorial geometry
Ivan Gutman
Abstract
Hexagonal systems are geometric
objects obtained by arranging mutually congruent regular hexagons
in the plane. Such geometric features are usually not considered
in secondary-school courses of mathematics, although these are
easy-to-grasp and probably interesting to students. In this
paper the elements of the theory of hexagonal systems are
outlined. We indicate some properties of hexagonal systems that
secondary-school students could prove themselves, as well as a
few less easy results and open problems.