From dik@cwi.nl Mon Aug 2 21:10:32 1993 Return-Path: Received: from charon.cwi.nl by life.ai.mit.edu (4.1/AI-4.10) for /com/archive/cube-lovers id AA06234; Mon, 2 Aug 93 21:10:32 EDT Received: from boring.cwi.nl by charon.cwi.nl with SMTP id AA20559 (5.65b/3.8/CWI-Amsterdam); Tue, 3 Aug 1993 03:10:23 +0200 Received: by boring.cwi.nl id AA23300 (4.1/2.10/CWI-Amsterdam); Tue, 3 Aug 93 03:10:22 +0200 Date: Tue, 3 Aug 93 03:10:22 +0200 From: Dik.Winter@cwi.nl Message-Id: <9308030110.AA23300.dik@boring.cwi.nl> To: cube-lovers@life.ai.mit.edu Subject: Diameter of cube group? I have now running (for about 60 days already) a program that implements Kociemba's algorithm to solve the cube. It tries to solve random configurations and stops when a solution of 20 turns or less is found. The random configurations are created by doing 100 random turns. Until now, with 9000 configurations tried, all proved to be solvable in 20 turns or less. This strongly suggests that the diameter of the cube group is at most 21, or perhaps 22; but not more. The figure of 9000 configurations in 60 days indicates that solution of one configuration takes slightly less than 10 minutes. This is contrary to what I thought was possible. Whenever I tried configurations they were mostly solved within 2 or 3 minutes. This suggests that the random configurations are more difficult to solve than what I and many others brought up as possible difficult patterns. But I still need to do some analysis on the ouput (now 3 Mb of data). Continuing and waiting for a config that requires 21 turns, dik -- dik t. winter, cwi, kruislaan 413, 1098 sj amsterdam, nederland home: bovenover 215, 1025 jn amsterdam, nederland; e-mail: dik@cwi.nl