Material added 28 Jun 2004
The great puzzlemaster, Nob Yoshigahara, has passed away. He helped both me and this site out a lot in the past few years, and I'm just one of hundreds of puzzlemakers he has helped, and one of the millions of puzzler solvers he has entertained. My latest Math Games column is about him.
Serhiy Grabarchuk: "Thank you very much for such a great article about Nob! I'd like to add that past year there was one very remarkable milestone in Nob's life. In 2003 (May 17, 2003) Nob received the Sam Loyd Award for Lifetime Achievement at that year's Association of Game & Puzzle Collectors (AGPC) Convention in New Haven. As he wrote to me about that Convention and Loyd Award receiving: "There was a paradise on this earth!" Some pictures from the New Heaven AGPC Convention (including several with Nob) you can find in the pages of the Games and Puzzles Gallery  AGPC Album at Bruce Whitehill's Big Game Hunter website.
Several people sent me puzzles for the contest I mentioned on 13 June.
Cihan Altay: Puzzle Design Tournament 2004
has ended. You can download the optimization puzzles, see the results
and best answers submitted, on the tournament website: http://www.otuzoyun.com/puzzledesign/.
The puzzle set for the 2004 Google U.S.
Puzzle Championship is well worth trying out. I especially
like the new puzzle types by Erich Friedman. Longtime solver here
Joseph DeVincentis is now on the US Puzzle Team. Congrats!
Have fun with WeiHwa in Opatija, Croatia.
My next major conference will be the Wolfram
Technology Conference. For anyone that comes, I'll be glad to
show my collection, lots of math stuff, and our Periodic Table
Table.
There is a special Issue of TCS
about "Combinatorics of the Discrete Plane and Tilings". Theoretical
Computer Science, Volume 319, Issues 13, Pages 1484 (10 June 2004)
An article on computational
origami was covered on Slashdot. The Particle Data Group blue book will be
sent out in August. It's a free book  add your name to the mailing
list if you have any interest in particle physics.
Patrick Hamlyn took a look at the 1248
enneominoes without holes.
Material added 13 Jun 2004
http://wpc.puzzles.com/
 The U.S. Puzzle Championship will be hheld on Saturday June 19, 2004
at 1pm ET. Please read the rules and register here
before June 17, 2004. Some warmup puzzles can be seen at Conceptis. A
whole book of these is the World
Puzzle Championships Omnibus.
Over 25 years ago, Elwyn R. Berlekamp,
John H. Conway, and Richard K. Guy set out to make the definitive book
on the mathematics of Games. They succeeded with their book Winning Ways.
It went out of print, and became quite valuable. Now, Winning Ways is
now back in print entirely. Volume
1, Volume
2, Volume
3, and Volume 4
are all available. I have one extra copy of Volume 3, which I
will give to whoever sends me the best gamerelated puzzle. Send Puzzle. On Numbers and Games is also
available.
My latest Math Games column
features 2D
Turing Machines.
My next one is about Egyptian Fractions  if you have something really
neat concerning Egyptian Fractions, please send it to me soon.
Another column I'm working on involves hemispheres. I hear the
word "Hemi" in car advertising too often to avoid a long
explanation. If you know any good hemisphere puzzles or trivia,
please let me know about it. For future columns, I'm pondering moire
patterns, the 12 queens problem, optimized paths, the projective plane,
venn diagrams, word lists, golf tournaments, mobile mechanics,
interactive fiction, hyperbolic tiling, iamonds, pi via billiards, k7
knots, folding tetrahedra, Harary's Pathos, and modern burr
puzzles. Write me if you
have any comments, ideas, or suggestions for future columns, or
corrections to past columns.
There is a very nice paper on Heesch's
Tiling Problem
in the latest American Mathematical Monthly by Casey Mann, the
University of Texas at Tyler tiler. Perusing MAA Focus, I found out
about their new Convergence
webpage.
William Paulsen's Calculator
Maze is very nice.
If you're curious about the shapes of dice
that have actually been made, dicecollector.com
has a full page about them. I'd like to learn more about the
32sided Czechoslovakian roulette die. With rapid prototyping,
some metal hexecontahedra could be made as a small project by one of
you. If anyone does, let me know, and I'll post your email
address here so you can take orders.
Material added 05 Jun 2004
The Bureaucratic
Nightmare
is a maze through red tape. Robert Abbott: "Just wanted to let
you know that there is now an interactive version of the Bureaucratic
Maze that you can play online. It's called the Bureaucratic Nightmare
and it was created by Eric Shamblen. To try it, go to my home page: http://logicmazes.com/ then go to the "What's new"
banner at the top, and follow the pointer."
I'll be attending the Wolfram
Technology Conference in Champaign IL on October 2123. I'll
be glad to show my puzzle collection and the periodic table to
anyone attending.
Material added 29 May 2004
2^24036583  1 is prime. A full news
release on the discovery can be seen at mersenne.org.
Material added 23 May 2004
Jan Kristian Haugland is
offering $100 in potential prizes to people that can better his current
finds in Grid Subgraphs.
JeanCharles Meyrignac: Just to
mention that I recently (11/11/2003) found a 9x8 grid with french
words. In France, it's considered as the Holy Graal by crossword makers
(verbicrucistes in french) ! List of
Definitions.
D
E C R O C H E S
E C O E U R A N T
R O N F L A N T E
A T T R I S T E R
P A R A P H E R A
E M A C I E R A S
R E I T E R A I S
A S S E N A S S E
Erich Friedman: Find a 83omino that
contains exactly 2004 rectangles of various sizes. Send Answer.
I used , the
8 Moebius Transforms for Complex Continued Fractions, to make the
following picture. It all starts with the three number on the complex
plane {0, 1, 2}. Three complex numbers will define a line or a
circle. Let one of the 8 transforms act on those three complex
numbers, and you'll get three new numbers that define a line or
circle. The below picture shows some of the ways of using up to 5
of the transforms on{0, 1, 2}. Piers Haken  "I’m
fascinated by the short
piece you wrote on the
relationship between klenian groups and complex continued fractions. I
have
written a program to do a realtime zoom into
an appolonian gasket using soddy
circles and I’d love to extend it to the Gaussian numbers."
Turns out that the math is pretty simple.
Material added 13 May 2004
Nyles Heise has built Langton's Ant
in Wireworld, along with many other
things. He also built a lovely Binary
Counter (as explained at Mathworld).
They are incredible to watch.
I made a Mathematical Crossword for my
latest Math Games
column, along with a rundown of the rules and records I know about.
Cihan Altay: PDT 2004 is starting. Send
your optimization puzzle until May 21st to compete. See the
Rules&Progress of the tournament on the tournament web site: http://www.otuzoyun.com/puzzledesign/
The Math Underground has
started up, with math tshirts, and some other stuff.
John Grint: I have a number of
identical rectangular sheets of paper. The sides
and diagonals of each sheet measure an exact number of millimetres, and
the sheets are less than 1 metre on each side. I can place a
number of
sheets side by side to make a long rectangle whose diagonal is also an
exact number of millimetres; alternatively, I can join a
(different)
number of sheets top to bottom to make another long rectangle
whose
diagonal is again an exact number of millimetres. How many sheets
of
paper do I need to make each of the long rectangles? (Send Answer)
Brad Pitt was recently asked about the
injury to his Achilles tendon. He damaged it severly enough to
cause a delay in shooting, while playing Achilles. "Stupid
irony," Pitt mumbled dismissively.
Material added 3 May 2004
My writeup on the Quantian
Distribution has lots of good information. Many of the
packages in Quantian are interesting to play with, such as the Surface Evolver by
Ken Brakke, which is an interactive program for the modelling of liquid
surfaces shaped by various forces and constraints. A good windows
program is Irfanview 3.91,
which will open any image format very quickly.
Math
Forge has added MathML, and it works quite nicely. The Math Underground has
started, which has some math tshirts. The Mathematical
Fiction site lists references to math in works of fiction. Erich
Friedman sent a puzzle based on his latest Math Magic
experiment" "Place the digits 1 through 9 in a 3x3 grid with the
operations of addition, division, and exponentiation in between the
digits to produce 3 horizontal and 3 vertical expressions, all of which
are equal to 16. Likewise, use the digits 1 through 9 with only
the operations of addition, subtraction, and exponentiation to give
every column and row equalling 7. Both solutions are unique, up
to reflection."
WeiHwa Huang and I attended Mensa Mind
Games in Chicago. He's a selfdescribed crazy gamer, and to show
his credentials he played and
reviewed every game. My thoughts coincide with WeiHwa's pretty
closely. My favorite game there was The Penguin Ultimatum,
which was fun, original, deep, and disarming.
Rick Shepherd has solved
my Chaos Tiles challenge.
Material added 19 April 2004
Robert A Hearn:
"Place four coins on the bottom row of circles (G, D, E, and R), so
that the letters MARTIN are exposed. Your challenge is to slide
these coins along the graph edges, covering the top row of circles, to
expose the letters GARDNER. Easy, right? There's a catch 
at no time are two coins allowed to
be next to each other along an edge.
You'll find this makes the task much more interesting. (And yes,
you have to slide the coins one at a time, all the way from one circle
to another!) For example, the G coin cannot move, initially  it
would wind up adjacent to the D coin. But D can move to T.
(or DT). Be careful to pay attention to all edges as you slide
the coins  the IR edge is particularly easy to miss. Good
Luck!" Answers and Solvers.
The Martin Gardner coin puzzle, by Robert A. Hearn.
A new column on Integer
Complexity is at Math
Games.
Minami Kawasaki: "Mr.Yasushi
Ireimake has written a fast program for solving the problem of
consectutive squares in squares. This
program can find the answer of 23(66*66) less than 10
seconds."
Berend
Jan van der Zwaag:
"Thank you very much for the puzzle!!! I like it very much. It
arrived
on Friday. My wife called me and said "there is a VERY LARGE package
for you!" She had no idea what was inside. :) The puzzle is even more
beautiful (and much bigger :)) than I expected. Please thank
Kate for
me for her beautiful piece of artwork." Kate Jones:
"Thanks for adding our link to your 37squares citation. I have now
made up a special page for them and would appreciate your putting the
full URL so people interested in ordering can find it immediately:
http://www.gamepuzzles.com/37square.htm" Only three sets
remain. Robert Reid and Berend
Jan van der Zwaag both solved placing squares of size 137 in a 133x133
square independently.
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Martin Gardner celebrates math puzzles and Mathematical Recreations. This site aims to do the same. If you've made a good, new math puzzle, send it to ed@mathpuzzle.com. My mail address is Ed Pegg Jr, 1607 Park Haven, Champaign, IL 61820. You can join my moderated recreational mathematics email list at http://groups.yahoo.com/group/mathpuzzle/. Other math mailing lists can be found here.
All material on this site is copyright 19982004
by Ed Pegg Jr.
Copyrights of submitted materials stays with the contributor and is
used with permission.
visitors since I started keep track. Yes, over one million.