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Date: Wed, 20 Dec 1995 06:24:28 -0500
From: der Mouse <mouse@collatz.mcrcim.mcgill.edu>
Message-Id: <199512201124.GAA04566@Collatz.McRCIM.McGill.EDU>
To: cube-lovers@ai.mit.edu
Subject: Re:  Physical Cubes and Models Thereof

> I would propose initially modeling the "larger group", where
> invisible changes in location and orientation are visible.  Number
> all 16 facelets of each face on the 4x4x4, for example.  [...].  For
> example, to make invisible orientation changes visible, you have to
> give a facelet four numbers rather than just one.

The only facelet for which invisible orientation changes are even
possible is the center facelet on an odd-order cube.  Other facelets
always have a fixed orientation with respect to the center of the face
they're on at the moment.  (On the 4x4x4, for example, if you mark
every facelet for orientation, you will find that each center facelets
always has the same corner to the face center, regardless of which face
it's on.)

					der Mouse

			    mouse@collatz.mcrcim.mcgill.edu