ref: 999e98b9b856ae4fc75b3ad33783488e33cdd426
dir: /sys/games/lib/sudoku/boards/hard-2005-05-19.su/
17.3..... ...1.48.. .34.29... 3........ ..72485.. ........6 ...87.92. ..25.1... .....2.85 175386492 926154873 834729651 359617248 617248539 248935716 561873924 482591367 793462185