Abstract:
In this paper we determine the nature
of separating quadrilaterals and hexagons
in quadrangulations of the sphere.
As one of the main results of the paper,
we show that if a quadrangulation of the sphere
contains a separating hexagon that is not induced,
then it contains a separating quadrilateral.
Key Words:
Hexagon, induced, quadrangulation, quadrilateral, sphere.
2010 Mathematics Subject Classification: Primary 05C10; Secondary 05C40.