How to Solve a Sudoku 16

Sudoku-16 is a bigger, more challenging version of Sudoku.

Sudoku is a popular Japanese puzzle in which you have to use logic to figure out where to place numbers in a 9-by-9 square without repeating any digit in a section, row, or column. Sudoku-16 is a challenging variation in which you use a 4-by-4 grid and place both the digits 0 to 9 and the numbers A to F. The key to solving Sudoku-16 is to not be thrown by the size of the puzzle and apply the same logic you would to solve a traditional Sudoku puzzle.

Instructions

1. Divide the puzzle into 4-by-4 squares. Look at the first square and determine which letters and numbers are missing from that square. Try to place letters and numbers into the first square by eliminating them from rows that already contain that letter or number. For example, if you are missing the letter A in the first 4-by-4 square and the first three rows of the puzzle already contain an A, you may be able to place it in the fourth row. Repeat this process with each square of the puzzle.

2. Repeat Step 1 until you cannot place any more letters or numbers into the puzzle. Pencil in the possible solutions for each empty space. Place a small version of the number or letter in the corner. For example, if you could put an A, C, or 9 in a space, write each of these in the corner of the space. If any space contains only one answer once you have penciled in all possible answers, put that number or letter into the square.

3. Use logic to eliminate numbers or letters from your list of possibilities for each square. For example, if two squares in a row contain only the letter A and the number 9, those two digits can be eliminated from other squares in the row.

4. Check for digits appearing only once in a row or column. If a digit only appears once, it is the solution for that square. For example, if you only have one letter A in a column, the A is the solution to that space.

5. Erase numbers from your lists of possibilities as you place them in the puzzle Recheck your lists and continue eliminating numbers and letters to solve the puzzle.

References

• Paul's Page: How to Solve Sudoku

Resources

• Puzzle Express: Sudoku 16