Icosagon

The icosagon, or ic, is a polygon with 20 sides. A regular icosagon has equal sides and equal angles.

Icosagons are the largest polygon currently known to appear in a CRF polytope that is not part of an infinite series, as augmentations of certain icosagon-based duoprisms are CRF. Also, uniform compound with hecatonicosachoric symmetry exist based on duoprisms using icosagons and their star forms.

Stellations

 * 2-icosagram (compound of 2 decagons)
 * Small icosagram (3-icosagram)
 * 4-icosagram (compound of 4 pentagons)
 * 5-icosagram (compound of 5 squares)
 * 6-icosagram (compound of 2 decagrams)
 * Icosagram (7-icosagram)
 * 8-icosagram (compound of 4 pentagrams)
 * Great icosagram (9-icosagram)