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Veternary - Magic Trick
An animal based who-is-who in which with the right three questions any animal becomes uniquely identified using a ternary "sieve". For the first 16 animals this also works in binary.
Peace Angel Maze Card
Full color original art maze card of an Angel seeking peace.
Hand of Art Stickers
Two removeable vinyl stickers of the artist's hand.
Troxes
Like Origami meets Lego. No scissors, tape, or glue. This modular paper cutout is based on triangular geometry and mates with neighbors (edge-connecting) to create tetrahedra, octohedra, and icosahedra. The resulting polyhedra can then mate once…
Polarizing Puzzle
Two rectangular sheets that filter light according to polarization- with a twist. Rotating the two sheets ninety degrees with respect to each other results in all light blocked as expected, but flipping over a sheet also gives a similar result. Does…
Akio's Dahlia Star Translucent
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.
Palindromes
Sudoku with some added rules. This puzzle can only be solved in conjunction with the gift "Entropy" by Neil Calkin.
Magic Pizza Guy
Solve these puzzles and get a pass to the Magic Castle.
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…
Warped-Grid Jig-Saw Puzzle
With a laser-cutter, it is easy to make one-of-a-kind jigsaw puzzles. The question then is what pattern of cuts to use. Here is a gallery of some experiments I have been making in which the cut pattern is based on a warped grid. A pseudorandom…
Octaroller
BUILD your OCTAROLLER ! from 3 parts square.
RACE your OCTAROLLER ! down the ramp in a straight line.
CHEER your OCTAROLLER ! with supplied cheering pom pom on a toothpick.
Octaroller is included in Geometric Foundations of Design: Old and New…
RACE your OCTAROLLER ! down the ramp in a straight line.
CHEER your OCTAROLLER ! with supplied cheering pom pom on a toothpick.
Octaroller is included in Geometric Foundations of Design: Old and New…
Great Questions for Great Conversations
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…
On account of…
14-sided and Skew 8-sided Dice
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.
G4G14 Exchange Gift (Martin Gardner Magic Trick)
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…
Flippe Top
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.
Golomb Rulers
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.
Travel Straws
Re-usable straws in a little keychain-round container with G4G logo (from 2021 conference that was postponed) on it.
Puzzle Menu
A puzzle hunt hidden inside an 8-page pamphlet.
The 14 Two-Color Frieze Symmetries in Mosaic Knitting
Mosaic knitting, a relatively new form of two-color knitting, has become popular because it is easier for the knitter than most traditional forms of color work. The price of this ease is an unusual set of restrictions on color placement for the…
Guess-o-matic
This DIY paper-engineered magic trick performs an astonishing feat of mentalism thanks to a bit of secret mathematics.
StarHex-14: Theo Geerinck's 14 Polystars
14 tiles consisting of hexagons with 0 to 6 equilateral triangles attached on their edges can be cut from card stock provided to solve the large collection of puzzle figures presented. Five colors, each tile shape is unique with one mirror pair.…
I AM THE RHOMBUS
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.
14 Blocks
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.
A Torus Without Diagonals
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…
The Accountant
Martin Gardner would sometimes wrap puzzles inside stories he concocted, such as with the book “The Numerology of Dr. Matrix.” The following puts my favorite puzzle in that tradition: The Accountant
by Barney Sperlin
by Barney Sperlin