14 Blocks
Puzzle
All you have to do is move the large 2x2 block to the bottom right hand corner by sliding the blocks. Do not lift, turn or twist any block.
G4G14
Marti Reis
G14-044
14 Rabbiducks
Puzzle
Recreational Math
The puzzle is to fit 14 “rabbiduck” polyomino pieces into an 8x11 rectangle. (Gardner wrote about polyominoes in multiple columns. The specific polyomino pieces used are inspired by the rabbit/duck illusion that Gardner called the Rabbitduck in his autobiography.)
14 “Rabbiduck” Pieces that look (crudely) like a rabbit or a duck depending on orientation.
G4G14
Haym Hirsh
G14-055
14-sided and Skew 8-sided Dice
Toy
Recreational Math
A fair 14-sided die in the form of a heptagonal trapezohedron and a fair 8-sided die ("Skew d8") in the form of a triangular dihedron.
Dice Lab
G4G14
Robert Fathauer
Henry Segerman
G14-031
4!-Fold Puzzle
Puzzle
Are there any polycubes that can be unfolded into exactly a rectangle? This problem was solved in 2019. The smallest solution forms a nice puzzle — fold the rectangle into a polycube!
G4G14
Bob Hearn
G14-061
A "Pick a Card" Card
Magic
Recreational Math
A card (roughly the size of an index card) with an image that contains 54 playing cards (some duplicates, of course!). A spectator chooses one of the playing cards and, after a few questions, the magician reveals the choice!
The premise is similar to the well-known “pick a number” cards where binary representations are used to identify a mystery number that a spectator has chosen. In this case, the spectator will select any card that he/she sees, and indicate the colors of the squares in which this card is found. The magician then reveals the thought-of card!
Instructions will be printed on the back of the card.
G4G14
John Harris
G14-050
A G4G14 Puzzle
Puzzle
Recreational Math
This is a paper ring with a number puzzle. The hint is actually the logo that is at the beginning (which of course will be right after the end when it's a ring).
G4G14
Skona Brittain
G14-014
A Torus Without Diagonals
Puzzle
Recreational Math
Cut-and-fold a polyhedron with 7 vertices, 14 faces, 21 edges, and a hole through it like a doughnut. A cube has internal diagonals that connect the diametrically opposite corners. By contrast, this polyhedron has no internal diagonals. There are three other 14-faced polyhedra like this. The only other known example of a polyhedron with no diagonals is the tetrahedron.
Akos Csaszar
G4G14
Gwen Fisher
Barry Hayes
G14-045
Abstract Photograph - Acura TL
Art
Recreational Math
One of my interests is abstract photography, using ordinary photographs as the “paint” and using spatial and mathematical transformations to create an image from one or more sources. One transformation that I’ve been exploring is “Inside Out”, which involves moving the center of the image to the outside and moving the edges of the image to the center. For some source images, the result is a pleasing abstract that doesn’t immediately resemble the source but which contains recognizable elements of the original when you look closely.
G4G14
David L. Kahn
G14-048
Akio's Dahlia Star Translucent
Art
I invented the Fibonacci Turbine in an origami way. The wing itself functions as a rotating shaft. The structure is so simple that it is robust. It can be used for many engineering applications.
G4G14
Akio Hizume
G14-023
Big Knot Variation
Puzzle
Burr puzzle designed by Oskar van Deventer (used with permission). For G4G14, this 14-piece puzzle felt appropriate. Contrary to the name of the puzzle, these exchange puzzles are in fact rather small.
<br />Solution is available on <a href="https://buttonius.com/solutions/big-knot-variation/index.html" target="_blank" rel="noreferrer noopener">https://buttonius.com/solutions/big-knot-variation/index.html</a>
Oskar van Deventer
G4G14
Peter Knoppers
G14-005
Build 14 Bridges
Puzzle
Game
Recreational Math
The puzzle is strongly related to the number 14.
The trick is based on a pythagorean triple.
The size of the puzzle is about 10cmx10cmx2.5cm, and it is made by MDF.
Goal: Put all bridges on the board.
G4G14
Ryuhei Uehara
Tomoko Taniguchi
G14-021
C.L. Dodgson (Lewis Carroll) Oxford Mathematician
Recreational Math
Word Play
Lewis Carroll, the nom de plume of the Rev. Charles L. Dodgson, a mathematics lecturer at Oxford, was also an innovator in recreational mathematics, magic, puzzles, cryptography, and inventions. His appearances in Scientific American began with mathematician Warren Weaver’s article in April 1956, and his name is mentioned over a hundred times in fourteen of Martin Gardner’s “Mathematical Games” columns. Using these as a springboard, topics will also include Carroll himself, the Wonderland/Looking-Glass dyad, Gardner, and their intertwining in The Annotated Alice.
G4G14
Mark Burstein
Stan Isaacs
Stuart Moskowitz
G14-056
Conway's Game of Life
Conway’s Game of Life needs no introduction to fans of Martin Gardner. Numerous examples exist in which a GoL “spaceship” object sends out smaller objects (“gliders”, etc.) that move away from the generator at a constant speed. That speed is set by the underlying nature of the GoL’s generations, because each such object can move no faster -- generation to generation -- than the unit distance built into the GoL model itself. In fact, the maximum such speed of propagation is called c or “the speed of light” in GoL terminology. In a typical computer running a GoL in a lab, the unit of time in the GoL of course has no fixed relationship to the unit of time marked on the lab’s clock on the wall. If the lab personnel were to double the rate of GoL generations (relative to the clock on the wall), the speed at which a GoL glider moves across the screen is also doubled (relative to that clock), but within the GoL universe itself, there is no change in speed.
G4G14
Nathaniel Johnston
Dave Greene
G14-027
Cube-it Puzzle
Puzzle
9 loose square wafers of plastic with a hole in the center of all but one that has a cylindrical pin. It is clear that the wafers can be stacked on the pin. 7 of the wafers have notches of various size in the edges. There are no hints included. Each wafer can be flipped or rotated in 4 positions in relations to each other and can be in one of 8 positions on the stack. The goal is to find out what it is.. and I'm not telling! The puzzle is 3d printed in white PLA, using two Creality CR10S printers. It was designed using Rhino and sliced using Simplify3D.
G4G14
Craig Newswanger
G14-013
Custom Zometool Struts
Puzzle
3D printed custom Zometool struts, and a Zometool ball.
G4G14
Aaron Siegel
Scott Vorthmann
G14-007
Entropy
Puzzle
Sudoku with some added rules. This puzzle can only be solved in conjunction with the gift "Palindromes" by Elizabeth Gallagher.
G4G14
Neil Calkin
G14-009
Flippe Top
Toy
This document describes how I designed a new kind of top, which flips not just once, but over and over. I call it a "flippe top". It can be made either from wood or by 3D printing.
G4G14
George Bell
G14-035
Free the Pearl
Puzzle
Applying the planar puzzle mechanism of the Magic Disc puzzle to a three-dimensional form yields an interesting and challenging coordinate motion puzzle.
Bruce Patterson
G4G14
John Partridge
G14-008
G4G14 Exchange Gift (Martin Gardner Magic Trick)
Magic
Recreational Math
Legacy
We, on behalf of ThinkFun, would like to submit a physical gift based on a personal letter sent from Martin Gardner to one of our founders, Bill Ritchie, in 1994. We will submit photocopies of the letter, which describes how to perform the magic trick. We will also include the pieces needed to perform the magic trick.
G4G14
Bill Ritchie
G14-032
Golomb Rulers
Recreational Math
A perfect ruler for daily use. In mathematics, a Golomb ruler is a set of marks at integer positions along a ruler such that no two pairs of marks are the same distance apart.
G4G14
Qingqing Mao
John Bohannon
Yuan Mei
G14-036
Great Questions for Great Conversations
Game
COVID sometimes gives in unexpected ways. Had G4G14 had taken place March 25 - 29, 2020, my exchange gift would have been a packet of four cards with StoryCorps® Great Questions for Great Conversations and a fifth card with a puzzle.
On account of COVID, many shipments were delayed including colorful envelopes and cards from IndianWeddingCard.com, which I had planned to send out with my 2022 New Year’s letter. Rather than saving them for sending my 2023 New Year’s letter, I have enclosed my G4G14 gift in one of the distinctive envelopes.
G4G14
Nancy Blachman
G14-030
Guess-o-matic
Puzzle
This DIY paper-engineered magic trick performs an astonishing feat of mentalism thanks to a bit of secret mathematics.
G4G14
Adam Rubin
G14-041
Hand of Art Stickers
Art
Two removeable vinyl stickers of the artist's hand.
G4G14
Mindy Korth
G14-019
How to Put This Design on an Egg
Art
Recreational Math
I have made a full-color, two-sided instruction sheet on how to draw the attached design on an egg, along with a laminated picture of one of my eggs that has adhesive on the back to become a sticker.
G4G14
Susan D. Jones
G14-002
I AM THE RHOMBUS
Puzzle
Recreational Math
In one package: the strip of triangles and brochure for this new flexagon. The colorfully illustrated brochure will include folding directions, flexing directions, and images of the different possible faces.
G4G14
Ann Schwartz
G14-043