Regruntled.com

Here are some sudokus made of squares with rainbow patterns. As usual, there are 9 different patterns. There are 4 horizontal or vertical patterns, 4 diagonal patterns, and one centered pattern. Click on the image for a new sudoku.

I like the way the diagonals sometimes line up, creating larger patterns that extend from square to square. The effect is similar to the Sudoku maze, except that with the maze everything always lined up, but here things line up only part of the time.

I keep running into the fact that 4 times 2 is 8, not 9. I need 9 patterns because it’s a sudoku, but the sudoku is made up of squares, which have 4 sides. I can rotate a rainbow square 4 ways, and I can rotate a diagonal rainbow square 4 ways. I always seem to come out one pattern short, hence the one centered rainbow pattern that sticks out visually. I’m not sure whether that’s a good thing or a bad thing.