Doughnut Sudoku
(Published on 24. September 2025, 23:59 by billybeth)
Doughnut Sudoku rules apply- ie box five contains no digits. All other boxes each contain all the digits from one to nine as do rows 1,2,3,7,8,9 and columns 1,2,3,7,8,9.
Digits along indicated diagonals sum to total given.
Boxes 2 and 8 are 3x3 magic squares where each 3 cell row,column and diagonal adds to the same total.
Each digit apart from the number 5 can reach every other cell on the grid with its same digit in exactly six chess knight's moves.
Black dots indicate cells with 2:1 ratio - not all dots are given.
To check answer fill in box five with ones in every cell.
Digits along indicated diagonals sum to total given.
Boxes 2 and 8 are 3x3 magic squares where each 3 cell row,column and diagonal adds to the same total.
Each digit apart from the number 5 can reach every other cell on the grid with its same digit in exactly six chess knight's moves.
Black dots indicate cells with 2:1 ratio - not all dots are given.
To check answer fill in box five with ones in every cell.
Solve online:Sudokupad
Solution code: top row
Last changed on on 25. September 2025, 16:19
Solved by Harold, benisjammin, SKORP17, Smartacus, paranoid, SEPHEN
Comments
on 25. September 2025, 16:19 by billybeth
clarification
on 25. September 2025, 12:24 by VitP
it is very easy to satisfy the knight's move rule.
the magic squares don't interact at all, ditto for boxes 4&6.
the little killers provide only weak constraints.
therefore, no restrictions can be found without populating the majority of the grid.
THEREFORE, this cannot possibly be level 2.
on 25. September 2025, 11:59 by VitP
suggestion: if you find the "strange" rule confusing, consider the corner cells.
