Invented by a Japanese teacher, Tetsuya Miyamoto, the KenKen puzzle adds another layer of challenge by introducing math to the traditional Sudoku.
KenKen Rules
1. Fill in each box in the easier puzzle with a number from 1 to 4; in the harder puzzle, 1 to 6.
2. Do not repeat a number in any row or column.
3. The numbers in each heavily outlined set of squares, called cages, must combine (in any order) to produce the target number in the top corner using the mathematical operation indicated.
