Today's morning mail (electronic) continues recent threads regarding the tetrahelix and the Richter Transformation. On synergeo, we've been discussing Bob Gray's colorful notes on these subjects, plus I brought up Gerald's finding that tetrahelix vertices, if they start rational, stay rational, but with no tetrahedron precisely juxtaposing (by translation) with any previous one.
I wrote a little Python program to generate tetrahelix coordinates in rational number format, using a tip from Adrian.
John Braley pointed out that the 3-tet boat (a short helix) is already an octahedron, just not a convex one. John Brawley complained that Bob's description of the transformation (to a regular one) is confusing. I think having Braley and Brawley, both Johns, on the same list is confusing, but I don't blame Bob.
I forwarded some of this material (electronically) to Julian, a Wanderer, an artist, and a physics student who did graduate work with buckyballs in Austria. Bob is a physics guy too.