Minimal Sudoku (Jim Gillogly)

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Sudoku puzzles are composed of nine 3x3 squares of the numbers 1..9 arranged in a 9x9 Latin Square. The object is to complete the square starting from a set of given numbers. The contestant must produce a generalized Sudoku puzzle with as few givens as possible for each size of Latin square. Each Latin square will be composed of congruent rectangles: four 2x2 squares in a 4x4 Latin square each containing the numbers 1-4, six 2x3 rectangles in a 6x6 square with numbers 1-6, eight 2x4 rectangles in an 8x8 square, and so on up to some convenient maximum, such as a 20x20 Latin square broken into 2x10 and 4x5 rectangles. http://www.csse.uwa.edu.au/~gordon/sudokumin.php Dodeka (12*12) Submit rectangular sudoku grids, so that the number of givens is minimal.