From dik@cwi.nl Wed Oct 12 21:55:07 1994 Return-Path: Received: from charon.cwi.nl by life.ai.mit.edu (4.1/AI-4.10) for /com/archive/cube-lovers id AA07797; Wed, 12 Oct 94 21:55:07 EDT Received: from boring.cwi.nl by charon.cwi.nl with SMTP id ; Thu, 13 Oct 1994 02:55:06 +0100 Received: by boring.cwi.nl id AA21510 (5.65b/3.8/CWI-Amsterdam); Thu, 13 Oct 1994 02:55:05 +0100 Date: Thu, 13 Oct 1994 02:55:05 +0100 From: Dik.Winter@cwi.nl Message-Id: <9410130155.AA21510=dik@boring.cwi.nl> To: cube-lovers@life.ai.mit.edu Subject: CFF 34, summary of contents CFF #34 came out, it ought to have been in June but is a bit late. Still, the editors expect the next issue in December. Summary of contents. Leo Links: On Folding Puzzles. A discussion about folding puzzles made from paper or cardboard that display a particular figure or text when folded. Frits Goebel and Bernhard Wiezorke: Problems for Einstein. They discuss a puzzle consisting of 8 octonimo's which is marketed as IQ CREATOR, MAGIC BLOCK or EINSTEIN PUZZLE. They show a few pretty patterns that can be formed with the 8 pieces. Vic Stok: Skyline Tetracubes. This discusses figures that can be formed from the 8 different pieces consisting of 4 cubes glued together. Jacques Haubrich and Nanco Bordewijk: Cube Chains. This discusses a number of puzzles. Each consists of 27 cubes connected to each other by an elastic string. The objective is to form a 3x3x3 cube. Bernhard Wiezorke: On Nob's L-Puzzle. This duscusses Nob's puzzle. It consists of 10 L shaped pieces, 3 squares high, 2 squares wide; all in the same orientation, one such piece 4 squares high (also the same orientation) and one 3 square high piece in different orientation (i.e. turned over). The objective is to fill a 7x7 square, turnover of the pieces is not permitted. Jacques Haubrich: Pantactic Patterns and Puzzles. This discusses an extension of the memory wheel. On the wheel the digits 0 and 1 are written such that when you look at 3 consecutive digits, all 8 different can be created. This can be generalized to n consecutive digits. It is well known (since N.G. de Bruijn) that 2^n digits are needed. An 2-dimensional extension was made by B. Astle who had a 5x5 square with a black-white pattern such that when you look at the 16 different 2x2 subsquares you will find all 16 different configurations. C.J. Bouwkamp made this into a puzzle (in the early 70's) as follows: You have 16 2x2 squares with all possible patterns. The puzzle is to put them together in a larger square such that the borders match. Rotation is *not* permitted. Torsten Sillke: Three 3x3 Matching-Puzzles. A discussion about three puzzles consisting of 9 squares that have to be put in a 3x3 square where some form of marking has to match. Jacques Haubrich: Cube 216. The puzzle Gemini consists of 10 pieces where each piece is made by joining two 1x2x2 blocks together. This is done in all possible ways. It is known that there are 50 possible ways to pack them in a 4x4x5 block. Yoshikatsu Hara extended this with 22 pieces that form all possible ways to join two 1x3x3 blocks together. One result is that there are (at least) 11 selections of 12 of these pieces so that they can be packed in a 6x6x6 cube in an unique way. There are more results and the author asks also for input. Chris Roothart: Polylambdas. Polylambdas are formed from the 30/60/90 degree triangle. Lambdas can be joined at corresponding edges. Joining along the hypothenusa is not allowed. There are 4 dilambdas, 4 trilambdas, 11 tetralambdas en 12 pentalambdas. These 31 pieces can fill a parallelogram of 4 by 31 units (the short leg is the unit). Many other problems are stated. Columns: Mark Peters: Books and Magazines (book reviews) Edward Hordern: What's Up? (details some new puzzles) ------ CFF (Cubism For Fun) is the newsletter published by the Nederlands Kubus Club NKC (Dutch Cubists Club). Membership fee is NLG 25 individual, NLG 80 institutional. (USD 1 ~ NLG 1.70). Applications for membership to the treasurer: Lucien Matthijsse Loenapad 12 3402 PE IJsselstein The Netherlands If you write, please add an international reply coupon (can be obtained at your post office).