- No Wikipedia article exists for the 19-gon. Why not create it? The values shown on this page are predicated based on the pattern of other n-gon articles. The name of the article should be Enneadecagon based on the list of polygons at https://en.wikipedia.org/wiki/Polygon.
- Icosagon (Wikipedia)
In geometry, an icosagon or 20-gon is a twenty-sided polygon. The sum of any icosagon’s interior angles is 3240 degrees.
