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Like Sudoku, solving a Kakuro puzzle involves investigating combinations and permutations. There is an unwritten rule for making Kakuro puzzles that each clue must have at least two numbers that add up to it, since including only one number is mathematically trivial when solving Kakuro puzzles.

The history of Sudoku dates back to an 18th Century Swiss mathematician's game called Latin Squares  (according to this article from the Economist) and some of the first number puzzles to appear in newspapers were published in France in 1895.