Comparing counts of triangulations and pointed pseudotriangulations
For a planar point set, is the number of pointed pseudotriangulations at least the number of triangulations, with equality only for convex position? A pseudotriangulation partitions its convex hull into polygons with three convex corners; pointedness requires an incident angle greater than a straight angle at every vertex.
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Problem statement
For a planar point set, is the number of pointed pseudotriangulations at least the number of triangulations, with equality only for convex position? A pseudotriangulation partitions its convex hull into polygons with three convex corners; pointedness requires an incident angle greater than a straight angle at every vertex.
Lean 4
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Background
Editorial selection inspected on 9 September 2026. Current research status has not been independently reassessed; consult the original source and subsequent literature.
- [1]The Open Problems Project — Computational geometry: Comparing counts of triangulations and pointed pseudotriangulations (inspected 2026-09-09) link
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