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MensekiMeiro Challenge. A Math Problem From Singapore Goes Viral: When Is Cheryl’s Birthday? A couple of months ago, it was a color-changing dress that blew out the neural circuits of the Internet.

A Math Problem From Singapore Goes Viral: When Is Cheryl’s Birthday?

Though it may not have quite the mass appeal, this week it is a math problem that is making bushels of brains hurt. It started with a posting on Facebook, by Kenneth Kong, a television host in Singapore. Photo. Glogin?URI= Glogin?URI= Puzzles created by Inaba Naoki. Inaba Naoki ist einer der kreativsten Rätselautoren der Welt.

Puzzles created by Inaba Naoki

Auf seiner japanischen Website hat er derzeit über 2000 Rätsel in über 400 Rätselarten ausgestellt, von denen wir mit seiner Erlaubnis einige übersetzt haben und hier anbieten. Die Sammlung wird laufend erweitert. This Page in English Zu jedem Rätsel gibt es ein Applet, mit dem die 4~5 Rätsel online gelöst werden können. Beim Drucken der jeweiligen Rätselseite werden alle Rätsel (meist) auf eine einzige Seite als Grafik gedruckt.

Weblinks und Quellen Quellen und Copyright Alle Rätsel stammen von Inaba Naoki und wurden auf seiner Website erstveröffentlicht. Danksagung Unser besonderer Dank gilt Franz Josef "Franjo" Schulte für seine Hilfe bei der Übersetzung der japanischen Texte – und überhaupt! Zeitschriften Ab Jänner 2011 werden in den Rätselzeitschriften Logic Puzzles und Logik Akrobat Rätsel von Inaba Naoki publiziert. Bücher Internet. Tangle (mathematics) In mathematics, a tangle can mean one of two related concepts: The balance of this article discusses Conway's sense of tangles; for the link theory sense, see that article.

Tangle (mathematics)

Two n-tangles are considered equivalent if there is an ambient isotopy of one tangle to the other keeping the boundary of the 3-ball fixed. Tangle theory can be considered analogous to knot theory except instead of closed loops we use strings whose ends are nailed down. See also braid theory. Without loss of generality, consider the marked points on the 3-ball boundary to lie on a great circle. Tangles often show up as tangle diagrams in knot or link diagrams and can be used as building blocks for link diagrams, e.g. pretzel links. Some operations on tangles: Left: A tangle a and its reflection -a. Optimal solutions for Rubik's Cube. A computer graphic of a scrambled Rubik's Cube There are two common ways to measure the length of a solution.

Optimal solutions for Rubik's Cube

The first is to count the number of quarter turns. The second is to count the number of face turns. A move like F2 (a half turn of the front face) would be counted as 2 moves in the quarter turn metric and as only 1 turn in the face metric. Move notation[edit] To denote a sequence of moves on the 3×3×3 Rubik's Cube, this article uses "Singmaster notation",[2] which was developed by David Singmaster. Lower bounds[edit] Analyzing Rubik's Cube with GAP. This is an updated GAP 4 version of a GAP 3 example by Martin Schönert, 1993.

Analyzing Rubik's Cube with GAP

An almost classical permutation group of small degree is examined with some elementary GAP commands. The output given here has been produced by GAP 4.4, the input is available in form of a plain GAP 4 input file. Ideal Toy Company stated on the package of the original Rubik cube that there were more than three billion possible states the cube could attain. Jaap's Puzzle Page. UPDATED31/12/2014.

Jaap's Puzzle Page

There are new pages on the Pyraminx Duo, the English Sixteen puzzle, Jushbox, Logi Toli, NHL Hockey Puck Puzzle, Ramka, Triplex and Mandorla, Woodn't Die, and Kwazy Quilt. I added Magic Color Puzzle to the 14-15 Puzzle page, Switch to the Switcheroo / Leaping Frogs page, the Chameleon Cube to the Peter's Black Hole page, an improved solution to my three colour loop problem on the Tantrix page, and an improved proof of theorem 3 on the The Mathematics of Lights Out page.

Finally, I added Javascript simulations of the English Sixteen puzzle, Logi Toli, Ramka, and Triplex / Mandorla. UPDATED 26/06/2013. The Mathematical Tourist: Oval Track Puzzles. The puzzle known as TopSpin consists of 20 circular pieces, numbered 1 to 20, filling and sliding along an oval track.

The Mathematical Tourist: Oval Track Puzzles

TopSpin was introduced by ThinkFun (formerly Binary Arts) in 1988. Pieces can be moved around the track in either direction, keeping their order. Or any four consecutive pieces can be maneuvered into reverse order. Visual Education Project. Comprar Juego de Rompecabezas de Metal Hanayama Cast Spiral. Hanayama Elk Cast Puzzle - Extremely Difficult - Extreme Puzzle Guru - the specialist online puzzle store. Puzzle Design Competition HOME. Electroplated Nanodots by Nano Magnetics. Magnetic toy nanodots with 236 magnets element. Sphere. Rob's Puzzle Page - Home. Welcome to Rob's Puzzle Page - an on-line mechanical puzzle collection / puzzle museum.

Rob's Puzzle Page - Home

I maintain this site to report on the world of mechanical puzzles, to have fun, and share information with my family, friends, and other puzzle-people. In addition to lots of pictures of puzzles, you'll find information about puzzles, many pointers to where to get them, and some help with how to solve them. Explore using the menu at the left of this (and the bottom of every other) page, the classification page, or the site map. Frabjous Puzzle - Puzzle. The Museum of Mathematics.