21
votes
Dominoroto-toto
First, let us define some things:
For simplicity, for partial boards presented (with ...), let's consider that the width is equals to or larger than the height. If ...
- 10k
14
votes
Accepted
The five problems of the six domino tiles
Problem 1:
Problem 2:
Problem 3:
Problem 4:
Problem 5:
- 28.2k
13
votes
Accepted
11
votes
Introducing Domidoku!
Final Solution(Though its already answered, I wanted to solve it on my own as a part of learning. Due to an ongoing problem with imgur, it took too long for uploading the solution)
SUDOKU Solution.
...
- 18.9k
11
votes
Accepted
A puzzle with dominoes
There was one idea I had that made constructing a solution a lot easier.
Here is the solution I came up with.
- 55.7k
10
votes
Accepted
Piece de Resistance - Two Boxes, Two Boxes of Letters
With a friendly nod to @jafe (who came very close), since an hour has gone by I figured it was fair game to post my own independent solution… Didn't want to be seen as sniping or piggy-backing!
This ...
- 155k
10
votes
9
votes
What is the largest domino ring that can be made?
In a ring,
The given dominoes have three 1s, three 2s, four 3s, three 4s, five 5s. So 1, 2, 4 and 5 occur an odd number of times.
- 55.7k
9
votes
Accepted
Domino tiling on 8x8 checkerboard with four squares removed
Here is my attempt at a proof.
First I'll prove a useful set of shapes that can be covered by dominoes when two opposite-coloured squares are removed.
Now let's apply this to the problem at hand.
- 55.7k
9
votes
Accepted
8
votes
Accepted
8
votes
Accepted
Introducing Domidoku!
I worked with @Techidiot's sudoku solution and solved the Dominosa:
The key to understand is that unlike regular Dominosa there are no tiles with same digits. and the grey cells indicate cells that ...
- 11.5k
8
votes
Accepted
Friday's Dominosa Problem
Here is the solution:
Explanation (red):
Continued (orange):
Continued (yellow):
Finally (green):
Thanks for making these puzzles and enjoy your well-deserved weekend!
- 28.2k
8
votes
When Beatrix stops placing dominoes on a 5x5 board, what is the largest possible number of squares that may still be uncovered?
Another way to do the proof of optimality:
Could there be a domino here?
- 10.5k
7
votes
Accepted
4 walls of domino tower
As noted in the comments to the question, the tiles in the picture form a standard set except for an extra 5/6 and a missing 6/6. If we assume the picture to be correct,
Otherwise, making the ...
- 21.8k
7
votes
A puzzle with dominoes
Here's another solution. I also used Jaap's clever restriction; it's much easier to verify the solution by hand after using that particular limitation.
This solution has twelves in the inside corners ...
- 80k
7
votes
Accepted
How many tilings by dominoes of this region?
the answer is
There are mendatory dominoes with the line :
- 7,175
7
votes
Accepted
Monday's Unmatched Donimoes Problem
Since the 'donimoes' are limited to moving along their long axis, I believe this can be done in 12 moves as follows:
Visually:
- 155k
7
votes
Accepted
7
votes
Accepted
Catch 21: Lies in Advertising
The lie is:
After all:
Extended answer: Furthermore, as @LannyStrack points out in comments:
But there's still more!
Explanation of logic for deducing points in the spoiler block above:
- 155k
6
votes
Accepted
Thursday's Unmatched Donimoes Problem
This seemed to work. There are a couple of spots where there are disconnected pieces during a move, but IIRC that was acceptable.
- 80k
6
votes
6
votes
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6
votes
6
votes
6
votes
Divide a board into two pieces without cutting a domino
Completion of proof:
Observe that because of parity there actually have to be two bridging dominoes for every pair of adjacent rows/columns. Now count them: 5x2 horizontal + 5x2 vertical: That's more ...
- 21.5k
6
votes
Accepted
Monday's Fujisan Problem
I wrote a program which brute forces this. It found a solution with a length of
The sequence is:
The code is here: https://github.com/timojch/FujisanPuzzleSolver
If the program is correctly written, ...
- 3,040
6
votes
When Beatrix stops placing dominoes on a 5x5 board, what is the largest possible number of squares that may still be uncovered?
The answer is
Proof of optimality:
- 994
5
votes
Accepted
5
votes
Accepted
Fridays's Unmatched Donimoes Problem
This was tricky! (The top right corner is particularly difficult to manoeuvre, avoiding putting the 2's and 1's together. The 0's and 1's at the bottom also pose similar problems...)
A winning set of ...
- 155k
Only top scored, non community-wiki answers of a minimum length are eligible