The Hidden Logic of Sudoku, a book by Denis Berthier, provides stimulating new insights into the popular game. It proposes new graphical representations and new resolution rules. Additionally, it sets new standards of rigor in the approach to Sudoku.

The “Hidden Logic of Sudoku” provides the first systematic perspective of the logical symmetries of the popular game. These are fully exploited to define new graphical representations, new kinds of resolution rules and a precedence ordering of the rules consistent with their logical complexity.

The set of rules defined in the book is illustrated with [Read More...]

In several media you could already read the announcement about the Sudoku Championship 2007 in the US.

The Philadelphia Inquirer announced it will hold the first national Sudoku championship in the fall at the Pennsylvania Convention Center. The championship, October 19-21, will be hosted by puzzle master Will Shortz and will be open to a national and international field of contestants for beginner, intermediate and advanced categories.

In addition to a spot on the U.S. World Sudoku Team, the advanced level winner will receive $10,000 plus expenses paid for travel and accommodations to the World Sudoku Championship in India. The [Read More...]

The people from the world famous Wrigley’s chewing gum and their online game website Candystand.com have leaped on the Sudoku with a casino twist.

This Casino-style take on the classic brain teaser Sudoku with the same rules only a different lay-out (numbers, chips and suits), different difficulty levels and much more.

Casino Sudoku has very nice graphics and lovely music. Happy Puzzling!

Tags: Sudoku

ReallyEvilCanine is his blogname and he is blogging from Munich in Germany.

At his blog called “A Day in a Life” he wrote a great article on how to solve Greater Than Sudoku’s which you can find at Killer Sudoku Online.

In almost 50 steps he will help you to solve Greater Than Sudoku’s. Using a simple code and a lot of colored images to show you how he solves Greater Than Sudoku’s.

It most have take a lot of work to work this out but it will [Read More...]

Via PR-GB.com I found an article about new Sudoku variants called Sudoku Extend Game.

In this article they only mention that Sudoku Extend has different forms squares, that there are 28 various boards – actually 28 separate games and the game receives new quality due to the new form of squares. New algorithms for solution are necessary.

There is no reference in the Sudoku Extend article to any example of Sudoku Extend or any website (more information about can be read in the article). Maybe they are talking for example about Spring Sudoku, [Read More...]

Play Sudoku with the features that the most serious Sudoku puzzlers demand.

New York Times Touch Screen Sudoku feature 835 puzzles by The New York Times Crossword Puzzle Editor Will Shortz: - Touch-screen technology and lightweight stylus make it easy to use anywhere. - Custom puzzle feature lets you input puzzles from books, newspapers, or magazines. - The puzzles herein have not appeared in The New York Times.

Buy Excalibur New York Times Deluxe Touch Screen Sudoku from Amazon.com. Happy Puzzling!

Tags: Sudoku | NYT

The Times Online has a special again with a lot of different Sudoku Puzzles (Classic, Children, Super Fiendish and Killer Sudoku’s).

On the front is a special Sudoku puzzles, that the teams in the World Sudoku Championships were solving. To solve this variant of Sudoku you have to place a digit from 1 to 9 into each triangular cell, so that it appears once in each outlined shape, and in one horizontal and two diagonal directions (jumping any gaps).

You can find more information and a link to download the Spring Sudoku Special (pfd format) [Read More...]