level: simple
..1...5....2.1.8......9........8....7.......59..7.3..44..8.1..7.1.3.2.6..6.....5. | initial |
671438592392517846548296731124685973736149285985723614459861327817352469263974158 | solved |
level: simple
http://www.sudokuwiki.org/Interesting_Sudokus 23 Clues, minimal "Battlement“ Discovered by Klaus Brenner