ref: cb474632d3f23de10fea2d70a4b4c98d8f3a3755
dir: /sys/games/lib/sudoku/boards/easy-2005-03-04.su/
5.236.1.. 9...8..26 .3....... ..86...7. ..58.74.. .7...19.. .......3. 72..3...4 ..6.182.9 582369147 917584326 634172895 198643572 265897413 473251968 859426731 721935684 346718259