"Sudoku Flexes Math Muscles"

Some math behind the popular math puzzles...

No addition or multiplication is used to solve the puzzle, but that doesn't mean no math is involved - it's just hidden under the surface.

Computer programs use logic to generate the puzzles and rank their difficulty. Mathematical thinking is required to reason to a solution. And in a recent study, mathematicians have been able to determine when a puzzle will have more than one solution.

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