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Date: Tue, 19 Aug 1997 01:55:51 -0400
From: michael reid <reid@math.brown.edu>
To: cube-lovers@ai.mit.edu
Subject: Re: isoglyphs

herbert writes

> With the pattern generator it's indeed very easy to find the isoglyphs. 

i'm still unclear about what your pattern generator does.  could you
describe what it does, for the benefit of those who haven't seen your
program?

>                                               By the way, Mike, it would
> be nice to complete the chapter "continous isoglyphs" by computing the
> shortest generators for them with your program.

i will do this soon.  right now the program is busy with T-symmetric
positions.  after that (or if there's a break) i'll give it the
continuous isoglyphs to think about.

there's one last pattern for which i could not find any isoglyph.
it's the 32 pattern of type

..*
*..
***

all others, except those previously mentioned as impossible (patterns of
corner type D, and the 21 and 23 types which we previously discussed)
have isoglyphs.  can your program find isoglyphs of this type, or show
that none exist?

mike