bronze badges votes answers views density of the number of points in a regular n-gon the polygonal numbers gives the number of points that fit into a regular r-gon: $$\text{p}_\text{n}\left(\text{r}\right):=\frac{\text{n}\left(\text{n}\left(\text{r} \right)-\left(\text{r} \right)\... number-theory fractions...
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