From: randall_rathbun@rc.trw.com Date: Tue, 04 Aug 1998 20:35:27 -0800 To: rusin@math.niu.edu Subject: Update to the Rational Box Dave: As of 1994, when I graduated from California State University San Marcos, in May, I had searched for the rational box, or integer cuboid, with the smallest side <= 1,281,000,000 with no success for a perfect cuboid. There were 30K+ solutions of the 3 types of cuboids found (body,edge,face) but not even any new information that John Leech was looking for regarding face pentacycles was uncovered. Sigh. This is so you can update your web page. - Randall L. Rathbun p.s: The search program was run twice, Torbjorn Granlund helped me, using MP arithmetic, it was exhaustive over the range, and it took 5 years computer time (IBM RS6000 workstations) ============================================================================== From: Dave Rusin Date: Tue, 4 Aug 1998 22:51:22 -0500 (CDT) To: randall_rathbun@rc.trw.com Subject: Re: Update to the Rational Box Thanks. Do you do a more or less exhaustive search, or do you parameterize the solution sets to partial configurations (e.g. boxes with integer sides and a couple of integer diagonals) and then eliminate those? I ask because I try such parameterizations from time to time and try "small" points of those types; right this minute my machine is walking over a few elliptic curves of rank 2 (which parameterize certain partial configurations) looking for complete solutions with dozens of digits -- sort of a shot in the dark, but hey, you never know! dave ============================================================================== Date: 5 Aug 1998 13:33:43 U From: "Randall Rathbun" Subject: Re: Update to the Rational To: "Dave Rusin" RE>> Update to the Rational Box 8/5/98 Dave: John Leech (when he was alive) and I did both kinds of searching. We did = use a parametric solution and looped over it. My exhaustive search was = completely exhaustive over all 3 types of cuboids, so there is NO possibility any = more of any perfect cuboid having any edge less than 1,281,000,000 . This is discouraging and some other results of the pythagorean generators = involved seem to point that the perfect cuboid does not exist. (too many symmetry requirements of the pythagorean generators) - Randall