MLC Board Meeting 45/17/03:

Figure 4.2 given below is the same as Figure 3.8 from the Sudoku chapter. The three moves a7: 2; b8: 7; and c9: 4 can each be considered as an incremental improvement. Each increases the total number of spaces that have been filled in, and none produces a region, row, or column with a duplicate digit entry. ................
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