Flippable Edges in Triangulations on Surfaces

Concerning diagonal flips on triangulations, Gao et al. showed that any triangulation G on the sphere with n ≥ 5 vertices has at least n − 2 flippable edges. Furthermore, if G has minimum degree at least 4 and n ≥ 9, then G has at least 2n + 3 flippable edges. In this paper, we give a simpler proof...

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Bibliographic Details
Main Authors: Ikegami Daiki, Nakamoto Atsuhiro
Format: Article
Language:English
Published: University of Zielona Góra 2022-11-01
Series:Discussiones Mathematicae Graph Theory
Subjects:
Online Access:https://doi.org/10.7151/dmgt.2377
Description
Summary:Concerning diagonal flips on triangulations, Gao et al. showed that any triangulation G on the sphere with n ≥ 5 vertices has at least n − 2 flippable edges. Furthermore, if G has minimum degree at least 4 and n ≥ 9, then G has at least 2n + 3 flippable edges. In this paper, we give a simpler proof of their results, and extend them to the case of the projective plane, the torus and the Klein bottle. Finally, we give an estimation for the number of flippable edges of a triangulation on general surfaces, using the notion of irreducible triangulations.
ISSN:2083-5892