Gattai (25 or larger)

Last change: 8 april 2018

There is a good website explaining all different kinds of overlapping Sudoku's:

Below are very big Sudoku arrangements.

All original created by Ruud van der Werf in 2006-2007

Shaolin X (25)

Up till now the SiSeSuSo Solver could NOT solve this Shaolin X 25 .

What a beast:

25=4x4+3x3 connected X-Sudoku's and the 26th is a scattered X-Sudoku.

All overlapping parts are clueless! And the diagonals also contain all 1-9.

Too many cells are open and SiSeSuSo is not smart enough yet.

In version V3 of the Solver are implemented:

- Naked/Hidden Pairs in diagonals and Box-diagonals elimination.
- the clueless scattered 26th Sudoku is implemented in SiSeSuSo .

but still not resulting in finding a solution

After a day of bruteforce/backtracking I stopped the search for a solution.

DOAG (85) The SudokuSolver excel is here (V2 version)

An arrangement of 85 Sudoku's in a 7x7 and 6x6 formation.

No X-Sudoku but the overlap areas are clueless .

4089 empty cells to fill.

Almost all can be done using basic eliminations and "box-to-rows/columns" or "pointing pairs".

No "Naked/Hidden Pairs" or "X-Wing/Swordfish" need to be used.

Only for the last 50 empty cells I have to use the brute-force searching part.

I don't know what elimination tactics are applicable here. Please let me know.

Some numbers on my Intel I5 :

- 4039 cells solved in 4:45 minutes:seconds and the remaining 50 cells in 40 seconds.
- SiSeSuSo is not intended to be very speedy.
- The "All Back" button to reset the arrangement to the original state needs 35 seconds eg.

On the rcbroughton forum you can find a second Gattai-85 Daddy of all Gattai #2,

which is completely solvable using only "box-to-rows/columns" or "pointing pairs".

Also included in the download as a second example-sheet.

MOAG (61)

On the rcbroughton forum you can find 2x "Mother of all Gattai" with size 61=6x6+5x5

Not tested/trying these yet.

Generator?

Maybe I should build a generator for these kind of puzzles (after I solved the Clueless Shaolin X).

There are not so many big ones - at least I cannot find them :-)

I expect that making overlapping Sudoku's are more complicated than generating single Sudoku's...

On the other hand, solving this by hand, you must be a bit sick or having too much time to spend days on this.

They are generated by a computer, I expect, so what is the fun of solving them by another computer?