AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |
Back to Blog
Double sided blank sudoku grid11/18/2023 ![]() ![]() The first pair we spot is an obvious pair in row 1. Can you spot any pairs or triplets in Example #42.4? We will begin with Step 1, identifying Pairs, Triplets & Quads. Once you fill in the options for the unsolved cells, your grid should look like Example #42.4 below: Example #42.4 STEPS 1-8 Now your grid should look like Example #42.3 below: Example #42.3 Example #42.3 FILL IN THE OPTIONS FOR THE UNSOLVED CELLS … In box 4 a 7 can only exist in C1R5, C2R5 or C3R5 therefore, a 7 cannot exist in C5R5. In box 3 a 6 can only exist in C7R1 or C8R1 therefore, a 6 cannot exist in C4R1, C5R1 or C6R1. Pencil a small 4 in the bottom of those two cells to indicate they cannot be a 4. In box 4 a 4 can exist only in C1R5, C2R5 or C3R5 therefore, a 4 cannot exist as an option in C7R5 or C9R5. Now your grid should look like Example #42.2 below: Example #42.2 MARK UNSOLVED CELLS WITH OPTIONS THAT CANNOT EXIST IN THOSE CELLS … This leaves only one cell in box 9 that can be a 9. The only cells in box 7 that can be a 9 are C2R9 or C3R9 therefore, C7R9 & C9R9 cannot be a 9. This leaves only one cell in box 9 that can be a 3. The only cells in box 6 (right center box of 3x3 cells) that can be a 3 are C9R5 & C9R6 therefore, C9R9 cannot be a 3. ![]() Now your grid should look like Example #42.1 below: Example #42.1 NOT-SO-OBVIOUS ANSWERS … The first obvious answer is C8R5=2 (cell in column 8, row 5). Start with the 1’s to see if there are any obvious 1-choice answers. FILL IN THE OPTIONS FOR THE UNSOLVED CELLS.MARK UNSOLVED CELLS WITH OPTIONS THAT CANNOT EXIST IN THOSE CELLS.Prior to utilizing techniques first complete the 4 Steps of Puzzle Preparation … May 2018, and June 2018Īs a reminder, the basic rules of Sudoku are that the numbers 1-9 must be contained and cannot be repeated in a row, column, or box, and there can only be one solution to the puzzle. Steps 1-5 are relatively common techniques and are explained in the TI LIFE articles above. Step 7: DAN’S CLOSE RELATIONSHIP CHALLENGE Step 4: XY-Wings & XYZ Wings – December 2015 Step 3: Sudoku Gordonian Rectangles and Polygons – November 2015 Step 2: Turbos & Interaction – October 2015 Step 1: Sudoku Pairs, Triplets and Quads – September 2015 Once you have completed the puzzle, to the extent that you have filled-in all obvious answers and have written all potential options across the top of the unsolved cells (PUZZLE PREPARATION), Dan recommends the following Steps to complete the puzzle. As always, the puzzle will require a keen eye! Puzzle #42 DAN’S 8 STEP APPROACH TO SOLVING ALL SUDOKU PUZZLES This month we return to a Sudoku puzzle format that will be most recognizable to you. ![]()
0 Comments
Read More
Leave a Reply. |