ref: 8749bcf34cd29eb5faa453117344b51acebd7a40
dir: /sys/games/lib/sudoku/boards/medium-2005-05-11.su/
.3..61... 8....25.. .298..... .5.....21 9.1...3.7 64.....5. .....327. ..62....5 ...48..3. 534761892 867392514 129854763 753948621 981625347 642137958 498513276 316279485 275486139