Just after that, I noticed that some diagonals passed through 5 boxes. They are 7 or 8 cells in length. Here are 2 example templates, 1 of 7 cells in length, the other 8 cells that show this.

- Code: Select all
`. . . . . . * . . . * . . . . . . .`

. * . . . . . . . . . . . . . . . *

. . . . * . . . . . . . * . . . . .

. . . * . . . . . * . . . . . . . .

. . * . . . . . . . . . . . * . . .

. . . . . . . . * . . . . . . * . .

* . . . . . . . . . . . . . . . * .

. . . . . * . . . . . * . . . . . .

. . . . . . . * . . . . . * . . . .

It occured to me that it might be possible to make a sudoku where all 8 of those diagonals has 5 occurances of the same digit.

With the help of a small computer program I found 3 different sudokus that have this feature. 2 of the sudokus are very similar, in fact I had to look closely to see the difference.

So, based on that I have produced some puzzles for people to try.

- Code: Select all
`Puzzle 1`

. . . 7 . . . . .

7 . 5 . . . 6 . .

. . . . 3 . . . 4

. 1 . . . . 8 . .

. . 2 . 9 . 3 . .

. . 6 . . . . 2 .

2 . . . 4 . . . .

. . 9 . . . 4 . 5

. . . . . 5 . . .

Puzzle 2

. . 6 . 3 . . 4 .

. . . 6 . . 3 . .

. 3 . . . . . . .

. . 3 . . . . 7 .

. . . . 5 . . . .

. 6 . . . . 8 . .

. . . . . . . 5 .

. . 1 . . 2 . . .

. 9 . . 8 . 1 . .

Puzzle 3

. . 1 . . . . . .

. . . 4 . 9 1 . .

7 . . . . . . 3 .

. . . . 5 . . . .

. 2 . 8 . 3 . 9 .

. . . . 4 . . . .

. 8 . . . . . . 1

. . 7 2 . 5 . . .

. . . . . . 7 . .

Hope you enjoy these Sudokus.