SuDoku (current version V3.70, May 2024)
Pencil Marks
The puzzle is displayed in an Excel spreadsheet, which works in most versions which support the Control Toolbox
The puzzle can be cleared
and a new one input manually and saved mid way for completion later.
Inputting a table is explained in the Rules tab
There are optional different levels of highlighting possible, with a user choice of colour scheme.
1) Original or sure entered numbers can be highlighted to simplify back tracking in case of an error.
2) Any single number at a time can be highlighted to simplify solving the puzzle.
3) Optional prompting can
highlight possible squares where a number can [or must] be safely input.
4) Tip: You can input several numbers in a square and use Sure/Unsure to size them and ignore the Error message, it may help for pairs
Optional prompting updates a separate table with "pencil marks" [possible numbers that can be input in the corresponding square].
Immediately obvious false inputs are signalled with an "Error" indication.
Latest Download xls file (150k) which contains a partially completed table
See the full rules and information in the Rules tab of the Excel workbook