About two years ago I was watching ‘Cracking the Cryptic’ during the lockdown. It was nice to see all the imaginative Sudoku-variants people would come up with, even though I myself have NEVER been any good at Sudoku, and the videos were relaxing to have on in the background. CtC was getting massively popular and I saw the potential for a large-audience: all I needed to do was to come up with a really original Sudoku idea. I got down to some programming and came up with the following badboys.
I cannot solve (and therefore cannot create) difficult Sudoku puzzles with pen-and-paper. However, thanks to brute-forcing Java code I created these puzzles to have only one valid solution each, so they are legitimate puzzles that hypothetically can be solved logically. I just do not know what the required steps are.
Meta Sudokus
So here’s the main idea I came up with. I originally called these ‘Higher Sudokus’ and later ‘Evil Twin’ Sudokus. I made them in three sizes because the full-size Sudoku was a nightmare, the miniature one was only fun for like ONE person in the CtC Discord server (the rest found it too much of a headache). So finally I made a micro 4x4 version which normal people can solve - though again it is probably too much of a brute-forcing grind.
I’m still very proud of this idea because it essentially puts the puzzler in the crafters shoes, and makes a puzzle out of the crafting process (valid Sudokus only have one solution).
Micrometa
Minimeta
Fullmeta
Rules
- Normal sudoku rules apply.
- Additionally, the numbers in the coloured squares must alone act as sufficient clues to generate a unique solution in normal Sudoku.
Explanation: Imagine you have already filled in the Sudoku grid completely (this is your solution). Next, imagine creating a copy of this solution and removing all of the numbers from it (including the starting clues) except for the numbers on the coloured squares. These remaining numbers must alone provide enough information to solve the Sudoku again (using normal Sudoku rules). If the remaining numbers to do not provide enough information (i.e. if there is more than one way to fill the rest of the Sudoku grid following normal rules) then your solution is invalid.
Miscellaneous Sudokus
So the meta-Sudokus were extremely frustrating for people to play, and therefore didn’t get featured on the Youtube Channel. Oh well! I was having a lot of fun with my sudoku generating code and spent a lot of time experimenting with adding other features to create something more human-friendly. I think I stopped trying to get featured on the channel by this point and was just doing this for my own amusement.
Splitdoku
- Normal sudoku rules apply.
- The diagonal must contain the numbers 1-9.
- Numbers must obey the inequalities.
- Numbers on ‘P’ squares must be prime numbers.
Equalities & Inequalities
- Normal sudoku rules apply.
- Diagonals must contain the numbers 1-9.
- Numbers must obey the inequalities.
- Numbers on ‘=’ squares are all the same.
Sensible Sudoku
- Normal sudoku rules apply.
- Diagonals must contain the numbers 1-9.
- Numbers must obey the inequalities.
The rest of the story
After posting these in the Cracking the Cryptic discord I posted them on the /r/sudoku subreddit. Some moderator then started removing the posts because he assumed I had stolen the Sudokus from the Discord. Apparently it did not occur to him that the Discord and Reddit accounts I was using were both the same person, i.e. me! 🤔
Okay, admittedly I didn’t help myself. The first Sudoku I had posted on the subreddit (for testing my metasudoku idea) was just a lazy modification of the Arto Inkala: a shortcut which everyone immediately noticed. After that, it is understandable that people would think I was just a thief! 🤣🤣