Gattai is a Japanese word meaning merged or fused. In the world of Sudoku, this term is used for overlapping Sudokus. A number indicates how many 9x9 Sudokus are in the puzzle.
The overlapping regions always contain complete boxes, although it is theoretically possible to overlap any number of cells. For a puzzle maker, partial overlapping boxes are more difficult to create.
Many of these overlapping patterns have been named by their publishers. For each pattern, the most commonly used name is listed first, followed by alternative names.
Gattai-2
Sensei
Sudokus: |
2
|
Overlapping boxes: |
2
|
Names: |
Sensei, TwoDoku
|
DoubleDoku
Sudokus: |
2
|
Overlapping boxes: |
4
|
Names: |
DoubleDoku, Gattai-Near-2
|
Gattai-3
Sudokus: |
3
|
Overlapping boxes: |
6 (5 x double, 1 x triple)
|
Names: |
Gattai-3, Triple
|
Gattai-4
Sohei
Sudokus: |
4
|
Overlapping boxes: |
4
|
Names: |
Sohei, Ring, Diamond
|
Butterfly
Sudokus: |
4
|
Overlapping boxes: |
12 (8 x double, 4 x quadruple)
|
Names: |
Butterfly, Gattai-Near-4
|
Flower
Sudokus: |
4
|
Overlapping boxes: |
9 (4 x double, 4 x triple, 1 x quadruple)
|
Names: |
(open) Flower
|
Gattai-5
Samurai
Sudokus: |
5
|
Overlapping boxes: |
4
|
Names: |
Samurai
|
Flower
Sudokus: |
5
|
Overlapping boxes: |
9 (4 x triple, 4 x quadruple, 1 x quintuple)
|
Names: |
Flower
|
Note: |
This is indeed exactly the same as Flower (4). The central sub-grid in flower (5) is superfluous since all its rows, columns and boxes are already defined by one of the other sub-grids.
|
Wing
Sudokus: |
5
|
Overlapping boxes: |
6
|
Names: |
Wing
|
Kazaguruma
Sudokus: |
5
|
Overlapping boxes: |
8
|
Names: |
Kazaguruma (Windmill)
|
Gattai-8
Sudokus: |
8
|
Overlapping boxes: |
8
|
Names: |
Gattai-8
|
Gattai-11
Shogun
Sudokus: |
11
|
Overlapping boxes: |
12
|
Names: |
Shogun
|
Gattai-13
Sumo
Sudokus: |
13
|
Overlapping boxes: |
16
|
Names: |
Sumo, Daimyo, Harakiri
|
Gattai-25
Shaolin
Sudokus: |
25
|
Overlapping boxes: |
36
|
Names: |
Shaolin
|
See Also