1256789 1346789 2345789 39: 1356789 2346789 40: 1456789 2356789 41: 2456789 42: 3456789 8 cells 36: 12345678 37: 12345679 38: 12345689 39: 12345789 40: 12346789 41: 12356789 42: 12456789 43: 13456789 44: 23456789 9 cells 45: 123456789 See also Kakuro Sudoku External links Too good for Fiendish? Then try Killer Su Doku - article in The Times Sudoku