The New Sudoku Players' Forum

[Guest]

Is it possible to have a 3x3 x-wing? Involving one number 3 times on three rows.

[Sue De Coq]

It is possible to generalize the X-Wings pattern further. More general patterns such as 'Swordfish' and 'Nishio' are discussed under the 'Solving Sudoku' topic on the Sudoku Programmers forum. I believe that the Pappocom software optionally supports Nishio but doesn't support Swordfish. The puzzles that appear in The Times certainly won't feature generalized X-Wings patterns.

[chabo]

Here you find an interesting part about generalized X-wings

http://users.pandora.be/vandenberghe.jef/sudoku/index.html?how2solve

or

http://www.daily-sudoku.tk