[geometry] In geometry, a decagram is a 10-sided star polygon. There is one regular decagram star polygon, {10/3}, containing the vertices of a regular decagon, but connected by every third point. ==Star figures== There are two regular decagram star figures: {10/2} and {10/4}, connected by every second and every fourth point respectively. =... Found on http://en.wikipedia.org/wiki/Decagram_(geometry)