The mathematics of Sudoku, a puzzle that boasts "No math required!"

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A very interesting article on Sudoku strategies and the underlying math. It makes for some good, heavy reading over the Labor Day weekend.

"The instructions that accompany Sudoku often reassure the number-shy solver that "No mathematics is required." What this really means is that no arithmetic is required. You don't have to add up columns of figures; you don't even have to count. As a matter of fact, the symbols in the grid need not be numbers at all; letters or colors or fruits would do as well. In this sense it's true that solving the puzzle is not a test of skill in arithmetic. On the other hand, if we look into Sudoku a little more deeply, we may well find some mathematical ideas lurking in the background."

Here is another look at the math underlying Sudoku - an order-3 Sudoku grid (the most popular type with 3x3 blocks) has almost 4,000,000,000,000 unique solutions.

Tags: sudoku, math, mathematics, puzzle, recreation, leisure, labor day weekend