## Nonomino Puzzles

There are a number of different variations on the Sudoku puzzle. One is even-odd Sudoku, where cells containing odd digits have a different background color than the even digits. Another is diagonal Sudoku, where the two diagonals form two additional groups of unique digits. There are also variations on size, such as 16x16.

But of all the different non-standard variations, the one that appeals to me the most is nonomino Sudoku, also known as geometric Sudoku. This variation most closely approximates regular Sudoku, but instead of nine 3x3 groups, it has nine groups in irregular nonomino shapes. Since the 3x3 groups in regular Sudoku are themselves nonominos, regular Sudoku is a proper subset of nonomino Sudoku.

How do you solve nonomino Sudoku puzzles? Exactly like you would solve regular Sudoku puzzles. However, because the nonominos in each puzzle are different, it may not be as easy to apply the short cuts you might be used to.

There's another difference between my regular puzzles and my nonomino puzzles. Although I like to generate regular puzzles with (at least) 4 degrees of symmetry, such symmetry seems pointless in nonomino Sudoku since there's no symmetry in the shapes of the nonomino groups.

As with the other groups of puzzles, the nonomino puzzles are freely available in printable form as PDF files. Each file contains 100 puzzles, with 2 puzzles per page. Difficulty of the puzzles varies, with some needing some of the advanced solving methods.

If you really enjoy these puzzles, consider making a contribution to support the continued existence of this web site. Click on the "Contribute to boldts.net" icon at the left to make a \$10 payment via PayPal. Think of how much you have to pay for Sudoku books in the store. And think about how many puzzles you can download from this site.