[next] [prev] [up] Date: Wed, 22 Aug 84 18:06:00 -0400 (EDT)
[next] [prev] [up] From: Dan Hoey <hoey@NRL-AIC >
~~~ ~~~ [up] Subject: An outer automorphism of the cube group

If you have a Rubik's cube where all the edges flip on each
quarter-turn, you can solve it by using bifocals when it's odd.

I noticed this while drawing a Hasse diagram of the subgroups of M. It
turns out that M has a similar automorphism, where the odd elements are
reflected through the center of the cube.

If anyone wants the Hasse diagram, I can send it--it takes about 30
minutes to draw in the lines, for which directions are included.

If you know whether there are other outer automorphisms of M, please
let me know.


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