From cube-lovers-errors@mc.lcs.mit.edu Fri Jul 2 13:23:14 1999 Return-Path: Received: from sun28.aic.nrl.navy.mil (sun28.aic.nrl.navy.mil [132.250.84.38]) by mc.lcs.mit.edu (8.9.1a/8.9.1-mod) with SMTP id NAA15540 for ; Fri, 2 Jul 1999 13:23:13 -0400 (EDT) Precedence: bulk Errors-To: cube-lovers-errors@mc.lcs.mit.edu Reply-To: From: "Noel Dillabough" To: "Cube Lovers List (E-mail)" Subject: Solution for the size 2 octahedron Date: Thu, 1 Jul 1999 17:48:12 -0400 Message-Id: <000001bec441$c8879680$29f5ddce@laptop> After playing with the size 2 corner moves based octahedron, I found that the solution for most of the edges is trivial, just a matter of putting them into place using standard puzzle moves. The only part of the puzzle that needs a special move is the final step that you may be left with a pair of faces that need to be switched: The following represent a tip of the octahedron, and sides A and B must be switched R-> | _____|______ | A | B The following move accomplishes this: Down Rotate Counterclockwise Up Rotate Twice Down Rotate Twice Up Rotate Twice Down Rotate Clockwise The "Up" and "Down" moves refer to the right half of the octahedron, cut through the middle of the tip and leaving the left half steady. The Rotate moves refer to rotating the tip in place. Anyone with a good notation for this and the size 3 corners based octahedron, or the side based size 2 or 3 octrahedra let me know. [Moderator's note: Isn't a corners-based octahedron just a face-based cube with the corners flattened and the faces made pointy? I think BFTDLR or BFUDLR would work for notation. --Dan]