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 a hundred of puzzles together with their full resolution paths. It suffices to solve almost any puzzle without making guesses or assuming the uniqueness of a solution. It has been fed into an Artificial Intelligence (AI) engine and a large database of puzzles has been processed, leading to a precise evaluation of the efficiency of each rule. The book is intended for both advanced Sudoku players (who will discover many new facets of the game and a new, systematic approach to the resolution rules) and for teachers or students of Logic or AI (who will appreciate the strict logical foundations).

The more puzzles you solve, the more you want to play — that's the secret of sudoku, the Japanese sensation that's sweeping the globe. There are dozens of sudoku puzzle books available, but this whimsically illustrated edition is specially designed for kids. Its 48 brand-new puzzles are geared toward players from the ages of 8 to 13, but anyone can enjoy them. All you have to do is fill in the squares with the digits 1 through 9 in such a way that each digit appears in each column, row, and large square only once. That's all there is to it! No math skills are needed, just reasoning and logic — and an appetite for hours of nonstop puzzle fun! Solutions appear at the end.

Get in on the next sudoku trend! Godoku--or sudoku word puzzles--are already beginning to appear in national newspapers. They offer an alphabetical variation on the conventional version, complete with a hidden word that’s revealed only when the puzzle’s complete. Anyone who knows sudoku will catch on quickly, because the game’s almost identical: the only difference is that instead of nine numbers, godoku has nine letters. And the grid still can be solved by logic alone. Some are straightforward, some are super-challenging, and all the words are arranged by category. A comprehensive introduction explains how these devilish new puzzles work.

"The Hidden Logic of Sudoku" provides the first systematic perspective of the logical foundations and of the symmetries of the popular game. These are fully exploited to define new resolution rules, new graphical representations and an ordering of the rules consistent with their complexity. The classical pattern of xy-chains has been extended into a homogeneous set of chain rules that, when added to a few elementary rules, suffices to solve almost any puzzle. These rules are illustrated with a hundred puzzles with their full resolution paths. A large collection of puzzles has been processed by Artificial Intelligence (AI) techniques, leading to a precise evaluation of the efficiency of each rule. This pedagogical book is intended for both Sudoku players (who will discover many new facets of the game and new rules - all set in a uniform conceptual framework based on patterns) and teachers or students of Logic or AI (who will appreciate the strict logical foundations).

Sudoku has taken America by storm! Now kids can enjoy the puzzle that keeps their parents' minds racing and pencils sharpened. This edition, designed for children 8 and up, begins with a sudoku lesson from Will Shortz and very easy 4 x 4 grids to warm up. Then young solvers advance to more challenging 6 x 6 grids and finally tradition 9 x 9 sudoku puzzles. Features: · 150 all-new sudoku puzzles · Four difficulty levels including smaller "kid grids" · Fun commentary and illustrations · Edited by legendary New York Times crossword editor Will Shortz · Big grids with lots of space for easy solving

Here it comes: a revolution in sudoku solving! This is by far the most complete guide to cracking these addictive puzzles ever produced, with tricks even the experts won t know. While most books might have a few pages of introduction before proceeding straight to the sudokus, this one covers it all: hidden pairs, naked pairs, X-wings, jellyfish, squirmbag, bivalue and bilocation graphs, turbot fish, grid coloring, and chains. Every single one is here, and much more too, including the exclusive Gordonian logic methods (Gordonian rectangles and Gordonian polygons) that will turn even the hardest puzzles into a breeze. Of course, there are hundreds of sudoku for practice. A very special addition is a reprint of the very first sudoku ever published in 1979, from "Dell Pencil Puzzles and Word Games" magazine!"

Just when you thought it was safe to pick up a pencil Killer Su Doku is based on the original Su Doku grid, with the same rules and numbers—1 to 9—but with an added deadly twist. This time there is an element of arithmetic involved and there are few, if any, clues. The aim is to not only complete every row, column, and cube so that it contains the digits 1 to 9, but to also fill in the outlined cubes so they add up to the same number. Hints to solve the puzzle are hidden in the joined squares where only one combination of numbers applies. In the case of joined squares, if the printed number is 3, it should be 1 and 2 that go into the squares. Likewise, in the case of three joined squares, if the printed number is 6, the only combination possible is 1, 2, and 3. To add one final fiendish level, each puzzle also has a time worked out by its Japanese creators so you can try to beat the clock.

Obsessed sudoku fans know that the newspaper puzzles just aren't enough to feed their solving addiction. But they don't have to worry, because they can pull out as many pages as they need from this sudoku collection and take them along to work on whenever the urge hits. It features nearly 160 puzzles to choose from, all 9x9 and of medium difficulty. But newcomers who want to plunge in will find all the tips, hints, and instructions they need up front to begin--including advice on eliminating squares using hidden pairs in rows and columns. Of course, all the solutions are right there on the back of the page, so you can check (or cheat) when needed.

Packed with dozens of the most difficult Hidden Pictures puzzles Highlights has ever created, this book is perfect for advanced puzzlers ages 8-12 looking for a next-level challenge! This jam-packed collection includes over 80 advanced Hidden Pictures puzzles, including photo puzzles, puzzles without clues, puzzles with scrambled clues and more. A great gift for anyone who loves a puzzle challenge, this engaging activity book is filled with more than 1,500 total objects to find. Kids (and grown-ups, too) will need to keep their eyes peeled searching through hilarious scenes like sloths playing ping pong, dogs enjoying a fiesta, and a fishy carnival. There are both full-color and classic black-and-white scenes to solve. Over 125 pages of puzzles adds up to hours of screen-free fun, great for keeping kids engaged during road trips or rainy afternoons at home. Plus, this book is crafted by puzzle experts to include learning benefits parents can count on. Searching for hidden objects is a great way for kids to develop important school skills like vocabulary, concentration and visual perception. Every puzzle solved will boost kids’ confidence and encourage them to take on new challenges.