A pentenn, or pentenneagon, is a figure formed by joining
five regular enneagons edge to edge.
is a figure with binary symmetry formed by an odd number of copies of
Here are the minimal known oddities for pentenns.
Please write if you find a smaller solution or solve an unsolved case.
Last revised 2011-06-05.
Back to Polyform Oddities.
Back to Polyform Curiosities.
Col. George Sicherman