From mreid@ptc.com  Wed Feb 21 18:14:30 1996
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Date: Wed, 21 Feb 1996 18:41:32 -0500
From: michael reid <mreid@ptc.com>
To: CRSO.Cube@canrem.com, cube-lovers@ai.mit.edu
Subject: Re:  < U, F, R > group

mark writes

> I am working on an engine to search optimal paths for < U, F, R > but
> it's not done yet. It's certainly within the bounds of computibility:
> 
> Size (u_f_r) = 170,659,735,142,400 (hmmm, 170 trillion maybe not!)

it should be possible to write a good searching program for this
subgroup.  use the filtration

              <U, F, R> ,  <U, F2, R2> ,  <>

(which is just the last two stages of the three stage filtration i
gave on may 22, 1992), and a kociemba-type searching method.
i don't know if it will be feasible to find optimal paths, but
this technique should get pretty close.

let us know what you find out!

mike