HDTenEightyP/NetNews huggingface dataset:
From: mab@wdl39.wdl.loral.com (Mark A Biggar)
Newsgroups: comp.theory
Subject: Re: Illustraion of graphs.
Date: 20 Nov 92 19:37:19 GMT
Organization: Loral Western Development Labs

In article <1992Nov20.004146.438@pasteur.Berkeley.EDU> hubertc@cory.Berkeley.EDU (Hung-Hsien Hubert Chang) writes:
>Hi! I would like to know if there is any picture books enumerating 
>graphs. (say from number n=4 to n=8)  (showing only the graphs 
>that are not isomorphic.)

This would be rather difficult as ther are an infintie number of graphs with
just 4 vertices.  You have to put a limit on the number of edges as well
to make the set finite.  You also need to specify you definition of isomorphic.
(i.e. are the vertices labeled, the edges, are the graphs directed, etc.)

--
MArk Biggar
mab@wdl1.wdl.loral.com
Newsgroups: comp.theory
From: frank@Cookie.secapl.com (Frank Adams)
Subject: Re: Cryptography and P=NP
Date: Mon, 23 Nov 1992 15:51:04 GMT
Organization: Security APL, Inc.

In article <Nov.22.18.04.19.1992.24744@remus.rutgers.edu> clong@remus.rutgers.edu (Chris Long) writes:
>In article <1992Nov20.000916.29325@CSD-NewsHost.Stanford.EDU>,
>  Vaughan Pratt writes:
>
>> 1.  I, Vaughan Pratt, agree that if P is not equal to NP then I will
>> pay you, Chris Long, $1000 on demand.  You agree that if P is equal to
>> NP then you will pay me $10,000 on demand.
>
>This sounds fine, but we should prepare a document that would be
>signed and notarized by both parties.  Sound fair?
>
>> Would you prefer 1995 or 2000 as the year of expiration?
>
>How about 1997?  That would be for 5 years.
>
>Is this the ultimate net.bet of all time?

Actually, while I think P is very likely not equal to NP, I think Vaughan may
have the better part of this bet.  If P=NP, an algorithm may be forthcoming
at any time.  Whereas, if P != NP, it is a very difficultproblem, and not
likely to be proved soon.
From: pdc@dcs.ed.ac.uk (Paul Crowley)
Newsgroups: comp.theory
Subject: Re: The P=NP question (was Re: NP Completeness Question
Date: 15 Nov 92 19:15:50 GMT
Reply-To: pdc@dcs.ed.ac.uk (Paul Crowley)
Organization: Do they make a washing powder called Caliban Automatic?

In article <Bxpv45.2I1@watserv1.uwaterloo.ca> nrswart@phonon.uwaterloo.ca (Nicholas R. Swart) writes:
>                       tswart@snowhite.cis.uoguelph.ca
>
>and I would be happy to send you copies of the research reports.

Presumably the guy's already under a snow of requests.  Could someone
post the reports?
  __                                ____
\/ o\ Paul Crowley pdc@dcs.ed.ac.uk \  /
/\__/ "I'm the boy without a soul"   \/
Newsgroups: comp.theory
From: skm8109@usl.edu (Mishra Subhada K)
Subject: Looking for BB implementation of NP-hard problems in C
Organization: University of Southwestern Louisiana
Date: Thu, 19 Nov 1992 19:40:10 GMT



Hello everybody,
 I am looking for any branch and bound implementation of solution
to NP-hard problems, preferably in C.

 I would like to make some comparisions of my version of the
program with existing implementations.

 If you have such a program and/or know of any source where I could
get one from, please respond.

 Thanks in advance.

Subha
(mishra@usl.edu)
Newsgroups: comp.theory,sci.math,sci.crypt
From: nrswart@phonon.uwaterloo.ca (Nicholas R. Swart)
Subject: Re: Research Reports by Prof. E.R. Swart - slight delay
Organization: University of Waterloo
Date: Tue, 17 Nov 1992 03:47:24 GMT

There has been a slight delay in converting the research reports to postscript.
Also, it turns out that one of the files is too large to be posted here,
even in compressed format. We are busy arranging an anonymous FTP account
where all three postscript files will be located. Everything should be set
by tomorrow afternoon, at which time we will post the FTP site.

Thank you for your patience.

Nicholas Swart
Dept. of Elec. and Comp. Engineering
University of Waterloo
Waterloo, Ontario
CANADA
N2L 3G1

Newsgroups: comp.theory,sci.math,sci.crypt
From: sgall+@CS.CMU.EDU (Jiri Sgall)
Subject: Re: Cryptography and P=NP and Re: Illustration of graphs.
Organization: Carnegie Mellon University
Date: Fri, 20 Nov 1992 19:34:24 GMT

In article <1992Nov20.000916.29325@CSD-NewsHost.Stanford.EDU>, pratt@Sunburn.Stanford.EDU (Vaughan R. Pratt) writes:
|> 
|> Are the following terms acceptable?
|> 
|> 1.  I, Vaughan Pratt, agree that if P is not equal to NP then I will
|> pay you, Chris Long, $1000 on demand.  You agree that if P is equal to
|> NP then you will pay me $10,000 on demand.
|> 
|> ...

In article <1992Nov20.004146.438@pasteur.Berkeley.EDU>, hubertc@cory.Berkeley.E\
DU (Hung-Hsien Hubert Chang) writes:
|> Hi! I would like to know if there is any picture books enumerating
|> graphs. (say from number n=4 to n=8)  (showing only the graphs
|> that are not isomorphic.)
|>

It looks like it is time to start comp.theory.humor :-)

-- Jiri Sgall
From: clong@remus.rutgers.edu (Chris Long)
Newsgroups: comp.theory
Subject: Re: Cryptography and P=NP
Date: 22 Nov 92 23:04:19 GMT
Organization: Rutgers Univ., New Brunswick, N.J.

In article <1992Nov20.000916.29325@CSD-NewsHost.Stanford.EDU>,
  Vaughan Pratt writes:

> 1.  I, Vaughan Pratt, agree that if P is not equal to NP then I will
> pay you, Chris Long, $1000 on demand.  You agree that if P is equal to
> NP then you will pay me $10,000 on demand.

This sounds fine, but we should prepare a document that would be
signed and notarized by both parties.  Sound fair?

> Would you prefer 1995 or 2000 as the year of expiration?

How about 1997?  That would be for 5 years.

Is this the ultimate net.bet of all time?
-- 
Chris Long, 265 Old York Rd., Bridgewater, NJ  08807-2618
Newsgroups: comp.theory
From: hermann@uran.informatik.uni-bonn.de (Hermann Stamm)
Subject: Re: "idiot"
Reply-To: hermann@uran.informatik.uni-bonn.de (Hermann Stamm)
Organization: Praktische Informatik III
Date: Mon, 23 Nov 1992 09:12:35 GMT

Hello!

In article <Nov.16.03.59.05.1992.2368@remus.rutgers.edu> Chris Long writes:
|> In article <1992Nov15.110945.19939@ringer.cs.utsa.edu>, Daniel Jimenez writes:
|> 
|> >> This proves that P=NP and all NP-complete and all other NP problems thus
|> >> have polynomial time algorithms.
|> 
|> Anyone who believes P=NP is an idiot.
|> 
|> Case closed.
|> -- 
|> Chris Long, 265 Old York Rd., Bridgewater, NJ  08807-2618


In my opinion it is ok for Chris to think so ("is an idiot"), but I think
if he posts such comments here in comp.theory he should also be forced
to tell the flaw(s) in the papers of E. Swart, which must exist if P!=NP !
They are available via anonymous ftp from snowhite.cis.uoguelph.ca
(131.104.48.1) under pub/comptheory/* . They are only 14/8/5 pages long,
thus it can't be difficult for him if really P!=NP !


Bye,

   Hermann.


P.S.:  I also think, that P!=NP, but I can't find any flaw in the papers til now.

Newsgroups: comp.theory
From: harold@odie.cs.mun.ca (Harold Wareham(Todd))
Subject: HELP: Obtaining MIT Tech Report
Organization: CS Dept., Memorial University of Newfoundland
Distribution: na
Date: Tue, 17 Nov 1992 14:50:38 GMT

Can anyone suggest how I can get a copy of the following tech report:

	Meyer, A. and Paterson, M. (1979)  With what frequency are
	 apparently intractable problems difficult? Technical Report
	 MIT/LCS/TM-126, MIT Laboratory for Computer Science,
	 Cambridge, MA.

Thanks in advance,

- Todd

Todd Wareham	harold@odie.cs.mun.ca	|"Success in science depends not
Department of Computer Science		| only on rational argument but
Memorial University of Newfoundland	| on a mixture of subterfuge,
St. John, NF, Canada	A1C 5S7		| rhetoric, and propaganda"
					|    - Feyerabend
Newsgroups: comp.theory
From: ld231782@LANCE.ColoState.Edu (L. Detweiler)
Subject: Anyone have C code for FFT?
Date: Wed, 18 Nov 1992 20:49:39 GMT
Organization: Colorado State University, Fort Collins, CO  80523

- - - 

Does anyone have C code for a FFT?  An anonymous ftp address?

tx.
--

ld231782@longs.LANCE.ColoState.EDU
Newsgroups: comp.theory
From: hubertc@cory.Berkeley.EDU (Hung-Hsien Hubert Chang)
Subject: Illustraion of graphs.
Organization: University of California, at Berkeley
Date: Fri, 20 Nov 1992 00:41:46 GMT

Hi! I would like to know if there is any picture books enumerating 
graphs. (say from number n=4 to n=8)  (showing only the graphs 
that are not isomorphic.)


Thank you.

Hubert
From: hopkins@cs.cmu.edu (Don Hopkins)
Newsgroups: comp.theory.cell-automata
Subject: Re: Symmetric Life rules
Date: 19 Nov 92 16:12:22 GMT
Article-I.D.: cs.Bxz10r.8x4.1
Organization: School of Computer Science, Carnegie Mellon University
Originator: hopkins@ECP.GARNET.CS.CMU.EDU

torbenm@diku.dk (Torben AEgidius Mogensen) writes:

>   I have been doing some investigations of what I call "symmetric" Life
>   rules. The idea is to have a set of rule for a variant of Conways Game
>   of Life, which are symmetric in the sense that a pattern of empty
>   cells in a field of set cells has exactly the same behaviour as the
>   corresponding pattern of set cells on an empty field. [...]
>
>   I have found such a set of rules and carried out some experiments with
>   these. The rules are also interesting in that the central cell in the
>   3x3 neighbourhood counts the same as the other cells. In short, given
>   that N is the sum sum of all the cells in the 3x3 neighbourhood, a
>   cell is generated for the next generation based on the following table
>
>	   N Cell
>	   0  .
>	   1  .
>	   2  .
>	   3  O
>	   4  .
>	   5  O
>	   6  .
>	   7  O
>	   8  O
>	   9  O

Your rule is similar to the "anneal" rule, but more turbulent. 
Anneal is a voting rule (that counts the 9 neighbors like your rule),
and votes with the majority -- unless it would be a close vote, then it
it votes the other way, to shake things up.  The lookup table indexed 
neighbor count for anneal is { 0 0 0 0 1 0 1 1 1 1 }, and the lookup
table for your rule is...... { 0 0 0 1 0 1 0 1 1 1 }.  The behavior of
both rules when given random input is to anneal the 1's and 0's into
bigger and bigger shivering blobs.  If a cell is surrounded by mostly 
the same color then it stays that way, but there is turbulance of
cells changing back and forth along the edges, which eats away at
sharp edges and smooths the blobs down, evaporating smaller blobs and
connecting the larger ones until it looks something like black and
white spotted cow hide. 

Rudy Rucker's "eco" rule uses "anneal" in one plane, in combination
with either "life" or "brian's brain" in parallel planes.  Think of
"anneal" as undulating land and water masses.  If the "anneal" plane
is land, it computes "life" in the parallel plane at that cell, so you
have all these critters running around on the land.  Otherwise it
computes "brian's brain" (a *very* active rule), so there are many
schools of fishes swimming around in the water.  It's even more 
interesting if you use "anti-life" (the bit reverse of "life", aka
"pro-choice") instead, since the interactions between "anti-life" and
"brian's brain" are much more exciting, as the background of
"anti-life" is stimulus to "brian's brain", and vice-verse.  

	-Don
Newsgroups: comp.theory.cell-automata
From: 100010.2243@CompuServe.COM (Joe Pritchard)
Subject: ANT21 for PC
Organization: The Internet
Distribution: inet
Date: Thu, 19 Nov 1992 19:06:47 GMT

I have a copy of this program posted on my board.  How do I post a
binary file up on to this list?  (I've not done it before!)

If someone can tell me how (I'm on Compuserve using CIM) then I'd be
delighted to post the program.

Cheers from Sheffield
Joe
From: heitkoet@lucky.informatik.uni-dortmund.de (Joerg Heitkoetter)
Newsgroups: comp.theory.cell-automata
Subject: Re:  Missed posts of parts of Spaceships in Conway's Life
Date: 16 Nov 1992 09:21:27 GMT
Organization: CS Department, Dortmund University, Germany
Distribution: inet
NNTP-Posting-Host: lucky

In article <9211152140.AA02300@zuni>, hiebeler@santafe.EDU writes:
|>   I would simply tell you to FTP those messages from the archive
|> of the CA newsgroup/mailing-list, but unfortunately the archives
|> had some problems and got erased a few times.  Last week I was just
|> starting to have them restored from tape though, so if you wait a
|> few days, those articles will hopefully be available for FTP.  I'll
|> send out a note when it happens.
|> 
|> --
|> Dave Hiebeler
|> Thinking Machines Corporation, and Santa Fe Institute
|> hiebeler@think.com, hiebeler@santafe.edu
I made a Texinfo version of the articles, and added an index,
it's available on request from David Bell -- I guess.

	-joke

--
Joerg Heitkoetter
Systems Analysis Group
University of Dortmund, Germany
(joke@ls11.informatik.uni-dortmund.de).
Newsgroups: comp.theory.cell-automata
From: yunes@fructidor.ibp.fr
Subject: Contact...
Organization: UFR d'Informatique - Universite PARIS 7
Date: Tue, 17 Nov 1992 11:28:19 GMT

	I'll be very happy if anyone could send me how to contact one of these
three persons :
	- Stephen Wolfram
	- Olivier Martin
	- Andrew Odlyzko

	(e-mail wanted)
	TNX
-- 
--------------------------------------------------------------------------------
Yunes Jean-Baptiste
LITP, IBP
Universite Paris 7
2, Place Jussieu
75251 Paris (FRANCE)
Tel : 44.27.28.40
e-mail : yunes@litp.ibp.fr
--------------------------------------------------------------------------------
Newsgroups: comp.theory.cell-automata
From: ledwards@leland.Stanford.EDU (Laurence James Edwards)
Subject: Re: popularizations ofcomplexity.
Organization: DSG, Stanford University, CA 94305, USA
Date: Mon, 16 Nov 92 23:50:54 GMT

In article <1992Nov16.075937.19475@reed.edu>, rseymour@reed.edu (Robert Seymour) writes:
|> [...]
|> 
|> 	As an all around introduction to Artificial Life, Levy's book is very  
|> good. It's not a technical description, but gives a good history and  
|> interesting anecdotes on the major advances in alife from pre1987 - early 1992.  
|> [...]

Yes I agree. Levy's style bugged me in places and some of the stuff borders on
hype and is somewhat misleading, but I think it's a good popular intro. -- if
only for the bibliography.

Larry Edwards
From: hurd@math.gatech.EDU (Lyman Hurd)
Newsgroups: comp.theory.cell-automata
Subject: Undecidability of configurations/progression
Date: 21 Nov 92 17:33:39 GMT
Distribution: inet
Organization: The Internet

Time for some definitions (sorry I was vague).

Let S be a finite set with distinguished (quiescent) element q.

Let S^Z (the hat symbol stands for superscript for non-TeX fans) be the set
of doubly infinite sequences of symbols from S.  Hence a configuration c,
is a function c: Z --> S. (Z the integers).

Defn 1: A configuration c is finite if there exists M such that c(i)=q for
all i with |i| > M.

The next definition may not have been obvious (sorry).

Defn 2: A configuration c is periodic (Golze's term) is there exists an M
and a P so that:

c(i) = c(i+P) for all |i| > M.

probably he should have called these ``eventually periodic''.  If this does
not suffice to explain things, I can sketch a proof.  It is not hard to
show that a finite coniguration need not have a finite predecessor (take
RULE 90 and a configuration consisting of a single non-zero site), and
furthermore some finite configurations can have non-periodic predecessors
(consider the zero map).  But if a finite configuration HAS a predecessor,
it must also have a periodic (in the above sense) predecessor.

References:

Some of Golze's results appear in:

U. Golze, ``Differences between 1- and 2- dimensional cell spaces'' in A.
Lindenmayer and G. Rozenberg (eds), ``Automata, languages, development'',
North-Holland (1976).

A more complete set of results appears in his dissertation:

U. Golze, ``Endlishe, Periodische, und Rekursive Zellulare Konfigurationen:
Vorgangerberechnung und Garten-Eden-Probleme'' Technische Universitat,
Hannover.

(for the mailing list, a refernce apropos my previous mailing on
injectivity and surjectivity)

S. Amoroso and Y. N. Patt, ``Decision Procedures for surjectivity and
injectivity of parallel maps for tesselation structures'', J. Comp. Syst.
Sci. 6 (1972) 448-464.
Newsgroups: comp.theory.cell-automata
From: mliggett@silver.ucs.indiana.edu (matt)
Subject: FAQ?
Keywords: FAQ
Organization: Indiana University
Date: Wed, 18 Nov 1992 19:51:35 GMT

is there a FAQ for this group?
if so, where?
thanks

-m
  

Newsgroups: comp.theory.cell-automata
From: james@panix.com (James Britt)
Subject: A-life book w/ Ca Lab for $55.00
Date: Thu, 19 Nov 1992 14:32:09 GMT
Organization: PANIX Public Access Unix & Internet, NYC

On the back page of the current Science News ( Nov 14) is an ad from
Arc Science Simulations.  They are offering various book/software
package deals.  One of them is Autodesk's CA LAb along with the
Levy book Artificial Life for $55.00  Perhaps not such a bad deal.

Arc can be reached at P.O. Box 1955N Loveland, CO 80539
Phone: 1-303-667-1168
Fax:   1-303-667-1105

James Britt
-- 
:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
Just another speed-metal vegetarian anarchist cyberhippie Zen Socratic...
Diblo Rules!                                        Hack The Wetware!
james@panix.com  .............................................................
Newsgroups: comp.theory.cell-automata
From: frank@Cookie.secapl.com (Frank Adams)
Subject: Re: Undecidability of configurations/progres
Date: Mon, 16 Nov 1992 20:29:09 GMT
Organization: Security APL, Inc.

In article <1e1q25INNmo3@seven-up.East.Sun.COM> hoppie@nemesis.East.Sun.COM writes:
>In article 100765@Cookie.secapl.com, frank@Cookie.secapl.com (Frank Adams) writes:
>>This depends on exactly how you define a GoE pattern.  If I have a pattern
>>which fits in an n by m rectangle, there are two questions I can ask:
>[...question (1) deleted...]
>>(2) is there any previous pattern whose next step is the specified pattern,
>>with everything outside the rectangle being blank?

This is perhaps subject to misinterpretation, especially with (1) deleted.
(2) says there is a pattern A, which generates exactly the pattern B as the
next step.  (1) Says there is a pattern A, such that the pattern it
generates, B', intersected with the rectangle, gives the target pattern B.
There was no intent to constrain the previous pattern A; quite the contrary.

>>Question (1) can be answered as described; however I believe question (2) is
>>the standard definition of a GoE.  And question (2) is, in fact,
>>undecidable.
>[...Proof concerning (2) deleted...]
>
>Suppose I have a 3x3 rectangle, in which I have placed a diamond.  I
>can tell you, with certainty, that there is a pattern with everything
>outside the 3x3 rectangle blank for which the diamond is the next
>step.  Thus for a specific configuration, of a certain size, question
>(2) is decidable.

An "undecidable" problem is one where there is no way of finding an answer
in general.  There may indeed be (and usually are) many individual cases
where the answer is known, one way or the other.

For example, there are many individual programs (of arbitrary length) which
we can prove will halt; and many others (also of arbitrary length) which we
can prove will not halt.  But, *in general*, there is no way to know when a
program will halt; some cases are hard.
From: james@panix.com (James Britt)
Newsgroups: comp.theory.cell-automata
Subject: Wolfram CA program, part 2/2
Date: 17 Nov 92 06:14:07 GMT
Article-I.D.: panix.1992Nov17.061407.16337
Organization: PANIX Public Access Unix & Internet, NYC

section 2 of uuencode 4.13 of file WOLFCA.EXE    by R.E.M.

M<@!?7V9I;&QC;VQO<@!?7V)A8VMC;VQO<@!?7VQI;F5S='EL90!?7V9I;&QS1
M='EL90!?7T]V97)38V%N0V]L;W(`7U]A=&5X:71C;G0`7U]C='EP90!?7V5XK
M:71B=68`7U]E>&ET9F]P96X`7U]E>&ET;W!E;@!?7W-T<F5A;7,`7U]N9FELW
M90!?7V]P96YF9`!?7V9M;V1E`%]?;F]T56UA<VL`7U]H96%P;&5N`%]?9&]S?
M97)R;F\`7U]D;W-%<G)O<E1O4U8`7U]S=&ML96X`7U]W<V-R;VQL`%]?=FEDA
M96\`7V1I<F5C='9I9&5O`%]?8T9L86<`7U]C0VAA<@!?7V9I<G-T`%]?;&%S.
M=`!?7W)O=F5R`%]?4F5A;$-V=%9E8W1O<@!?7U-C86Y4;V1696-T;W(`7U]AN
M=&5X:71T8FP`7U]T=7)B;T-R=`!?7V-V=&9A:P!?7T%(4TA)1E0`7U]!2$E.U
M0U(`5T],1D-!+D,`5T],1D-!`')U;&5N=6UB97(`8VAO:6-E`&-O;&]R<S(`&
M8V]L;W)S`')U;&5T86)L90!D=6(`9'5P;&EC871E,@!D=7!L:6-A=&4Q`&%R(
M<F%Y,@!A<G)A>3$`8P!Y`%E325I%`&UE;G5C:&]I8V4`1W)A<&A-;V1E`$=RB
M87!H1')I=F5R`$5R<F]R0V]D90!X`$U!4TL`;G5M8F5R`&QE=F5L`&9L86=S1
M`&9D`&AO;&0`8G-I>F4`8G5F9F5R`&-U<G``:7-T96UP`'1O:V5N`&9P`&1E-
M<V-R:7!T:6]N`&)I=`!S8W)E96X`>@!M96YU7W-T<G5C=`!W8VAA<E]T`$9)/
13$4`9G!O<U]T`'-I>F5?=`!?/
``
end
sum -r/size 863/916 section (from first encoded line to "end")
sum -r/size 46248/43397 entire input file
-- 
:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
Just another speed-metal vegetarian anarchist cyberhippie Zen Socratic...
Diblo Rules!                                        Hack The Wetware!
james@panix.com  .............................................................
Newsgroups: comp.theory.cell-automata
From: MCINTOSH@UNAMVM1.BITNET ("Harold V. McIntosh")
Subject: Basins of attraction.
X-Unparsable-Date: Tue, 17 Nov 92 00: 30:46 MEX
Organization: The Internet
Distribution: inet
Date: Wed, 18 Nov 1992 10:18:24 GMT

Andrew Wuensche <100020.2727(at)COMPUSERVE.COM> (Mon, 16 Nov 1992 08:23:16
EST) remarks:
>
> For finite CA with periodic boundary conditions there is a proceedure.
> Checking if a state is a G of E follows from computing its pre-images,
> if any. This can be done without exhaustive testing. The proceedure is
> described for 1-D CA (and the software included) in my recently
> published book, (see below). The G of E density in state space of a
> given CA rule is approx predictable by the rule's Z parameter. For most
> of rule-space with very few exceptions (the limited pre-image rules),
> most states in state-space are G of E states.
>    If anyone out there gets around to reading the book, or
> experimenting with the software, I would welcome comments or
> discussion.
>
Well, I have ordered a copy of the book; delivery has been promised for
January or February. In the meantime, it is only possible to conjecture
the contents of the book, and the relationship of the procedures to those
of E. F. Moore, G. A. Hedlund, M. Nasu, Erica Jen, or even myself. It is
well established that for one dimensional cellular automata, Gardens of
Eden are absolutely computable; difficulties lie in two dimensions and
beyond. In fact, there is no need to restrict to periodic boundary
conditions; the procedures serve as well for quiescence at infinity or
for boundaryless (that is, unrestrictedly infinite) automata.
-
It is necessary to commiserate with a remark made by Burton Voorhees here
recently about his article on this topic having disappeared into a black
hole. Two articles of my own have suffered the same fate. Is this traffic
entirely one-way?
-
In the meantime, here are a couple of questions in the way of making a
discussion. 1) Unless the counterimages are balanced, there must be a
Garden-of-Eden. Presumably this coincides with your 'limited pre-image
rules' remark above, and immediately foredooms most automata to have
Gardens of Eden.
-
2) In my early calculations of the variance in the number of ancestors,
there appeared to be a gap between the rules of zero-variance and the
others? Have you observed such an effect? Is it real (I later decided
that it probably wasn't)?
-
In any event, I look forward to seeing the book. To formulate our ideas
about automata well, it is convenient to have compilations of data to look
at. I have probably turned to the appendices in Wolfram's book more often
than I have consulted any of the other parts.
-
Harold V. McIntosh             |Depto. de Aplicaci'on de Microcomputadoras
MCINTOSH@UNAMVM1.BITNET        |Instituto de Ciencias/UAP
mcintosh@unamvm1.dgsca.unam.mx |Apdo. Postal 461
(+52+22)43-6330                |72000 Puebla, Pue., MEXICO