Charlemagne
(Published on 26. November 2021, 13:30 by manushand)
To help celebrate the World Chess Championship 2021,
currently being contested in Dubai,
this Chessboard Sudoku puzzle was adapted from a Blitz game
played online in 2019 by the current World Champion,
the great Magnus Carlsen.
This is one of nearly 200 Chessboard Sudoku puzzles available on the Chessboard Sudoku Website.
This one is rated "Challenging"; there are puzzles ranging from "Training" to "Difficult".
White to Move and Deliver Checkmate
- Standard Sudoku Rules Apply
- Chessboard Sudoku
- A chessboard is set upon the Sudoku grid (one row and column of the 9×9 Sudoku grid is not covered by the chessboard). The chessboard shows the position of pieces during the course of a chess game. Some number of legal, valid chess moves have been made. The pieces started the game from their normal starting positions. White and Black made moves in turn, and the pieces reached the positions shown in the puzzle.
White Pieces Moved UP in Number. When any White piece moved, the Sudoku digit on the square where it ended its turn was one greater than the Sudoku digit where it began the turn. (For example, if the White piece stood on a 2 before moving, it could only be moved onto a square containing a 3.)
Black Pieces Moved DOWN in Number. When any Black piece moved, the Sudoku digit on the square where it ended its turn was one less than the Sudoku digit where it began the turn. (For example, if the Black piece stood on a 2 before moving, it could only be moved onto a square containing a 1.)
This Restriction Applied to Both Pieces When Castling. If a player used a move to castle, both his King and Rook moved onto the correct digits.
Sudoku Digits Also Matter in Check and Checkmate. A king is not in check unless the Sudoku digit where it stands is the digit that the checking piece could legally move to on its next turn.
In this puzzle, this means that the single move that will be made from the depicted position — the move that delivers checkmate — must be made by a White piece moving to the correct digit that will give check (and deliver checkmate) to the Black king. - EXAMPLE
- The White pawn now on the e3 square could only have started the game on e2. The Sudoku digit on e3 must be one greater than the digit on e2. This means that e2 could not possibly be 9, nor could e3 be 1.
- Solve Online
- Chessboard Sudoku Website
Solution code: Row 4 (chessboard rank 6); nine digits
Comments
on 29. November 2021, 19:46 by mijlobbetiw
Very nice puzzle! I love the combination of retrograde analysis (and the interplay of the puzzle rules with this analysis). I'll be sure to check out the site some more in the coming days :)
on 27. November 2021, 14:46 by henrypijames
The online solve page shows no grid in mobile Chrome-based browsers, and even less (nothing except the title) in mobile Firefox-based browsers.
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manushand: Thanks for the information @henrypijames - I don't have much talent when it comes to adapting a site for mobile browsers, so I cannot promise I can fix it that easily, but I will see what I can do and any assistance from anyone out there with that talent and interest would sure be welcomed!
