[next] [prev] [up] Date: Tue, 21 Jan 92 23:27:28 -0700 (PST)
[next] ~~~ [up] From: michael reid <reid@math.berkeley.edu >
~~~ [prev] [up] Subject: Re: Rubik's cube dice tops (Spoiler)

a while ago (last month), Dan (hoey@aic.nrl.navy.mil) writes:

Last week ronnie@cisco.com (Ronnie Kon) challenged us to find Rubik's
cube patterns with dice pips for 1, 2, and 3 on the three pairs of
opposite sides. He claimed it could be done in fourteen HST, where
one HST is a turn of a face or center slice by 90 or 180 degrees. I
responded that it could be done in thirteen HST. Here is how. I will
use this opportunity to practice the enhanced Varga Rubiksong I
described (unfortunately with many typos) on 22 Feb 90.

The (only such) pattern is the composition of Four-Spot and Laughter.
We have long known the processes

[ description deleted ]

This uses only 13 HST. This is also the shortest process I know of in
the normal metric: 18 QT, which is not so bad for the combination of

here's a shorter way. in the "flubrd" notation, use:

D' F^2 R U^2 F^2 B^2 D^2 R^2 L' F^2 U' D^2
which is 11 "HST" (which i call "slice turns").  this is also 12
"face" turns, but 20 quarter turns.  this can also be done in only 14
quarter turns as follows:
                            F^2 U D F B U D F B U D F B'     (*)

note that this can easily be obtained from the well-known manuever for
                              ( F B  C_U )^6                (**)

where C_ means "turn the whole cube" (as in Bandelow's book). note
that this manuever reorients the cube. then manuever (*) is just the
"flubrd" translation of the manuever M_F (**) M_F' (without the cube
reorientation), where M_ means "turn the middle slice," again, as in
Bandelow's book.

here's a question for those out there with 5x5x5 cubes: have you
noticed that the stickers seem to be more happy on the floor than on
the facelets of the cube? the more i use my cube, the more restless
they seem to become. does anyone know of a good cure for this? i'm
thinking of taking them all off, cleaning off the glue (or gum or
whatnot) and gluing them back on, using a stronger glue. anyone have
any suggestions for what kind of glue? i'll let you know how my
experiment works.


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