Ok, I admit it, these pages are merely an excuse for me to try out Cinderella, a nice multiplatform Java application by Kortenkamp and Richter-Gebert for setting up this sort of animation. The black spots are anchor points, that you can drag around to produce different sets of circles with the same tangency pattern.
But anyway, there is some interesting math involved in constructing the circles above:
See also Paul Kunkel's tangent circles page for even more animated constructions.
From the Geometry Junkyard,
and recreational geometry.
David Eppstein, Theory Group, ICS, UC Irvine.
Last update: Sunday, 13-Jan-2002 14:05:07 PST.