Based on an inductive definition of triangulations, a theory of undirected planar graphs is developed in Isabelle/HOL. The proof of the 5 colour theorem is discussed in some detai...
Three types of geometric structure--grid triangulations, rectangular subdivisions, and orthogonal polyhedra-can each be described combinatorially by a regular labeling: an assignm...
We consider the problem of generating all ideals of a poset. It is a long standing open problem, whether or not the ideals of any poset can be generated in constant amortized time...
Abstract. We consider the problem of designing succinct representations of labeled graphs (we consider vertex labeled planar triangulations, as well as edge labeled planar graphs a...
Pointed pseudo-triangulations are planar minimally rigid graphs embedded in the plane with pointed vertices (adjacent to an angle larger than π). In this paper we prove that the ...