optimize/finch udg girth 30
optimize/finch udg girth 30: a task in MathConstructOptimize-Envs-harbor (Harbor dataset). Place $n = 30$ points in the plane. Their unit-distance graph $G$ has an edge between two points iff their Euclidean distance is exactly 1. Require that $G$ is not 3-colourable (chromatic number at least 4)…
The task
Place $n = 30$ points in the plane. Their **unit-distance graph** $G$ has an edge between two points iff their Euclidean distance is exactly 1. Require that $G$ is **not 3-colourable** (chromatic number at least 4) and **maximize the girth** of $G$ (the length of its shortest cycle).