From mreid@ptc.com Fri Feb 23 17:07:38 1996 Return-Path: Received: from poster (poster.ptc.com) by life.ai.mit.edu (4.1/AI-4.10) for /com/archive/cube-lovers id AA05550; Fri, 23 Feb 96 17:07:38 EST Received: from ducie.ptc.com by poster (5.x/SMI-SVR4-NN) id AA07793; Fri, 23 Feb 1996 17:03:11 -0500 Message-Id: <9602232203.AA07793@poster> Received: by ducie.ptc.com (1.38.193.4/16.2.nn) id AA13439; Fri, 23 Feb 1996 17:34:47 -0500 Date: Fri, 23 Feb 1996 17:34:47 -0500 From: michael reid To: cube-lovers@ai.mit.edu Subject: superflip in 20f jerry asks > A 24q process is known for superflip. It is known that superflip is > greater than 19f. Is a 20f process known for superflip? on may 17, 1992, dik winter gave ) Superflip: ) (13+7=20): F B U^2 R F^2 R^2 B^2 U' D F U^2 R' L' U B^2 D R^2 U B^2 U in my exhaustive search for superflip maneuvers of length <= 19f, several (but not all) branches of my search found maneuvers of length 20f. all were equivalent to dik's under the three operations * conjugation of the sequence by a symmetry of the cube * cyclic permutation of the sequence * inversion of the sequence perhaps it is the case that dik's maneuver is "unique" up to these operations. mike