From: Laura Helen <laurahelen@delphi.com>
Newsgroups: sci.math
Subject: Re: Points on a Sphere
Date: Sat, 24 Jun 95 18:26:46 -0500

From:	IN%"njas@alice.att.com"  "N J A Sloane"  8-MAY-1994 07:46:10.43
Announcement: Tables of Points on Spheres

For many years we have been running (low-priority) programs to
search for the best ways to place N points on a sphere in d dimensions.
These tables, which appear to be more extensive than any
presently available, can now be accessed electronically.

The main tables are of packings (with N <= 130, d = 3,4,5),
but there are also tables of coverings, minimal-potential
arrangements, arrangements which maximize the volume of the
convex hull, packings with icosahedral symmetry, all on the sphere.
There are also tables of minimal-energy clusters of N spheres in d-space,
and clusters which attempt to minimize the Lennard-Jones potential.

Much of this material will be published in a book ("Spherical Codes",
in preparation), but in view of the considerable recent interest
in these problems, both on the net and in journals, we are making
these tables available before the book is completed.

The tables are in netlib, and can be accessed by e-mail, ftp or mosaic:

1. By e-mail: to see what is available, send messages like
         send index from att/math/sloane
(or from att/math/sloane/packings, or att/math/sloane/packings/dim3, etc.)
to netlib@research.att.com.  To obtain one of these codes, send a message
such as
send att/math/sloane/packings/dim3/pack.3.92
to netlib@research.att.com.

2. By ftp: connect by ftp to netlib.att.com, login as anonymous,
use your e-mail address as password.  Type
   binary
   cd netlib/att/math/sloane
You can then use "ls" to see what files are available,
"get" to fetch them, "cd" to move to subdirectories, etc.,
and "quit" to quit.

3. From a mosaic document viewer, you can get
directly to the material.  Open an URL address such as:
   ftp://netlib.att.com/netlib/att/math/sloane/index.html.Z
   ftp://netlib.att.com/netlib/att/math/sloane/packings/index.html.Z
   ftp://netlib.att.com/netlib/att/math/sloane/packings/dim3/index.html.Z
This will give you a screen of short descriptions of all the items
available.  Clicking on one gives you the document, which
can then be saved in a file.

We would appreciate hearing of any improvements to these tables;
all such improvements will be credited in the tables.  Send them
to either of the first two authors.


N. J. A. Sloane (njas@research.att.com)
R. H. Hardin (rhh@research.att.com)
Math. Research Center, Room 2C-376,
ATT Bell Labs, Murray Hill NJ 07974 USA

Warren D. Smith (wds@research.nj.nec.com)
NEC Research Corp., Princeton NJ USA