Jim Propp asked:
What are those colored circles? (I see yellow, purple, green, blue, and red when I look at this picture closely.) Are they added just to give the cheese extra pungency? I temporarily forgot how to control the coloration of separate curves. Macsyma defaults to a certain sequence for the first 5, and then black. Those teeny ones got sorted into the first positions by a duplicate deleter (blush).
|z - n/d - i/d^2| = 1/d^2, for every reduced rational n/d.
Looks to me like there's a factor of two missing here. Ouch, right. |z - n/d - i/d^2/2| = 1/d^2/2 .
[...] gives you a tree in which every circle in the gasket in the region bounded by the four initial circles occurs once as a node.
Tnx! That could have saved me a megabyte or two. --rwg (I'd give an answer to the point of K exercise, but I haven't worked on it yet.)