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Build 14 Bridges
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.
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.
C.L. Dodgson (Lewis Carroll) Oxford Mathematician
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…
Celt Decision Maker
This wobbly spinner also called a "rattleback" features a physics defying unpredictability. Which makes it perfect for equally unsure decision making. Includes one 3¾" long rattle back and one 4½" wide decision disc.
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…
Cube-it 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…
Custom Zometool Struts
3D printed custom Zometool struts, and a Zometool ball.
Eastern Forest Playing Cards
Text by: David G. Haskell,
Illustrations by: Ellen Litwiller
Illustrations by: Ellen Litwiller
Entropy
Sudoku with some added rules. This puzzle can only be solved in conjunction with the gift "Palindromes" by Elizabeth Gallagher.
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.
Four Bar Ellipse
This mechanism demonstrates a surprising way to generate an ellipse by using a four-bar linkage. The shape of the ellipse can be defined by the path the intersection point of the two crossing bars follows. This fact is analogous to another neat way…
Free the Pearl
Applying the planar puzzle mechanism of the Magic Disc puzzle to a three-dimensional form yields an interesting and challenging coordinate motion puzzle.
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…
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.
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…