Hi
Recently I asked the question:
> I have a question, I hope this makes sence. ;) On a "nxnxn"
> tetrahedron with period 2 or period 3 turning or a "nxnxn" octahedron with
> period 3 or period 4 turning, can the orientation of any of the center
> triangles change when the puzzle is solved? If so, where does this
> start to happen. I know from "experience" that this is not true on
> a pyraminx.

Well, if you believe proof by example on a simulated puzzle, then
Tetrahedron period 2 turning: never happens
Tetrahedron period 3 turning: starts when n=4 with center triangle
Octahedron period 3 turning: starts when n=4 with center triangle
Octahedron period 4 turning: starts with n=4 with center triangle

New versions of my pyraminx and octahedron puzzles will be out soon
to reflect this.

Cheers,
      --__---------------------------------------------------------------
     /  \ \   /           David A. Bagley                                \
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