# Tag Info

Accepted

### Cover 63 squares of a chess board

These should do it: Just to show another example:
• 5,140
Accepted

Explanation:
• 33.3k

### How can 3 queens control the white squares?

I think this arrangement works for the bonus question:
• 1,683
Accepted

### How can 3 queens control the white squares?

I think this will do it
• 126k
Accepted

### A lonely pawn on the chessboard

Strategy: How this works:
• 5,856
Accepted

• 1,418
Accepted

### Black wants to go first!

Proof: Initially, there are an even number of knights on white squares (namely, there are two of them, at b1 and g8). Every time a knight moves, the number of knights on white squares either ...
• 31.6k

### Chessboard Rook Problem

There are more ones. Proof:
• 839
Accepted

### Dominos on a checkerboard

Looks like: Thanks to @Gamow's comment, this number's maximality can be proved by self-contradiction of the assumption that it is not maximal. Any more dominos would cover all 64 squares. Assumption ...
• 21.5k

### Two Knights, two Bishops, two Rooks and two Kings on a 4x4 chessboard

I'm not trying to solve the puzzle, I'm just interested in how many solutions there are, since the OP claims he doesn't know. I brute forced it with a program. There are First of all, there are ...
• 1,935
Accepted

### A chess board with numbers

The smallest sum that can be achieved is Because Reasoning
• 126k
Accepted

### 16 pawns on a chess board with no three collinear: how do I go about solving this?

The Algoritm is : Then Here is the complete solution from Achim Flammenkamp Ph.D. There are totally 57 solutions
• 17.7k
Accepted

### Mutilated chessboard

I believe this works as a short proof.
• 8,586
Accepted

### Could you solve a chessboard math puzzle at gunpoint?

Suppose that we have a chessboard with the desired properties. Find the greatest number in each row. Out of these numbers, let the smallest be $m_i$ in row $i$. Find the smallest number in each row....
• 33.3k
Accepted

### Desegregate the Knights

Give these names to all the squares: 163 4 8 725 Each number can only be accessed by way of the numbers before and after it (where 8 wraps around to 1). That ...
• 141k
Accepted

### Chessboard Rook Problem

There are Proof: Now I bet the ratio of good to bad is I wrote a little Python program (possibly buggy, so apply some skepticism, but I've tested the bit most likely to have bugs and it seems OK) ...
• 113k

### Chess solitaire: The King's longest walk

First solution - 50 moves Second solution - 59 moves Current solution - 66 moves (beaten by Retudin - 70 moves and Rewan Demontay - 139 moves) Moves:
• 17.9k

### Switch The Knights

I found a solution that uses 16 moves. After exhaustively checking that there is no solution in 14 moves, I conclude that 16 moves is optimal, because after any odd number of moves the number of ...
• 13.4k
Accepted

### Two Knights, two Bishops, two Rooks and two Kings on a 4x4 chessboard

I hope I didn't make any mistakes: Edit : Replace queens by king
• 524
Accepted

### Playing with one Queen on a chessboard

We can work backwards to figure this out: Conclusion:
• 141k

### The coolest checkerboard magic trick

This indeed is an old puzzle. One possible source (but certainly not the first one) is: Andy Liu: Two Applications of a Hamming Code The College Mathematics Journal 40, (Jan 2009), pp. 2-5 The ...
• 44.9k
Accepted

### The Popular Letter Chessboard

The rules of the question state that: On your final grid, a letter (actually several is also mathematically possible) will be more frequent than all the other letters. Your aim is that this letter ...
• 109k

### The Knight's Romp

I have a computer program for solving packing problems, and found a way to use it to solve this problem. One of the solutions it found is below: Note that this is very close to the attempted solution ...
• 46.1k
Accepted

• 13.9k
Accepted

### Tiling a Chessboard with tetrominos

It is not possible. The area of a $10 \times 10$ checkerboard is $100$, so it takes $25$ T pieces to have the same area. The checkerboard has the same number of red and black squares, but each piece ...
• 7,056

### Two Knights, two Bishops, two Rooks and two Kings on a 4x4 chessboard

Here is mine with passive kings, some minutes late :
• 3,070
Accepted

### Switch The Knights

You need at least 16 Moves. Let's make the task visually more simple. The initial board is: a4 b4 c4 a3 b3 c3 a2 b2 c2 a1 b1 c1 We cut it into 12 cells ...
• 15.9k

### Four fanatics and one checkerboard

I'm not sure why you'd need ANY sort of dissection for this.
• 2,737

### Black wants to go first!

While (as other answers proved it) it is impossible to solve this just by using knights, the problem can still be solved. Matthew says "As I want to play white, my first move isn't really a secret. ...
• 1,684