Killer sudoku adds boxes to sudoku puzzles which sum up to a certain number. (ex. https://sudoku.com/killer/expert/) For boxes with 3 or even 4 numbers summing to a ...
"Crook's Algorithm.pdf" exists here as a convenience to the user under fair use ... Current state of the project: I've implemented everything in Crook's paper up until the section "A Sudoku Puzzle ...