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How do I determine whether a 5x5 Lights-Out puzzle is solvable without trying to solve it?
To test if a 5x5 Lights Out pattern is solvable, you need to check two things. First look at the top, middle and bottom rows, at the first two and last two lights - the 12 lights bolded here:
[1, 0, ...
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18
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A Trivial Pursuit #25: Meta-Analysis
The overall answer is a very fitting trivial pursuit:
Or is it 20 words? (Or does the hyphen make it 21?)
Which happens to be the
How did we get here? Many probably saw this outright but I was ...
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16
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160 foxes are stuck on an island with 1 chicken. Will the chicken be eaten?
Let's start with a different scenario:
Now,
Therefore,
However,
I'm beginning to see a pattern here:
Therefore, in our original scenario with 160 foxes,
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9
votes
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7
votes
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Minimum Races for Top 3 horses
I think
races suffice to get the group of the top 3 but we won't necessarily know the order among them.
Start out as you said with making 6 groups of 6 horses and race each group. Then race the the 6 ...
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votes
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6
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Equality-breaking function
$f(x)$ is a function that:
Verification:
There is probably some more precision in the definition that I'm missing (to explain the last property), but I'm quite confident the general idea is in the ...
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votes
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Another puzzle combination (feat. Kakuro)
Well, that's an unusually neat Kakuro solution:
Presumably the other puzzle is something that involves
Yep, apparently it's called
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5
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A fun and simple Nonogram... ...with a cipher
Even though it wasn't part of the original question, in the comments OP gave out this invaluable nugget of information:
Since the nonogram was definitely difficult enough to warrant such trickery, ...
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4
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4
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Equality-breaking function
As mentioned in juathalf's answer, the definition of the "function" $f$ is that
But what is the most inclusive possible domain of $f$? A first attempt at answering that is to simply say ...
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A Hokuro, but with a twist!
Solved nonogram (black denotes filled cells, grey denotes empty ones):
Hokuro with colourings included (grey denotes "black" cells this time, white denotes empty ones):
Filling in single ...
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A 6x6 table with nothing filled out?
The completed grid:
Where do we start?
Let's start solving:
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A Hidato, but with no given numbers? #2: 5x5
First we solve the nonogram
There are
Then we see that only one of the
Then the two
Since the yellow
Now the yellow
Finally the red
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3
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Filling in an 8x8 minesweeper grid with mines (Day 8: Not a single mine)
The completed grid:
Solve path:
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2
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2
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Knights and knaves variations
"You can only ask one of us. It’s in the rules. And I should warn you that one of us always tells the truth and one of us always lies."
*"Two guards are standing before two doors. One ...
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A question from Bob to Bob
Brief:
Day 1: Bob shares with John a question about day 2 of a fact that John can physically control. John leaves the room.
Day 2: Nothing/Something happens.
Day 3: John enters the room. John read ...
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2
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What is the next logical step I can take when solving the Nov. 30 2023 Sudoku in the Wisconsin State Journal?
There are a number of techniques that are available at this stage. The first one that jumped out to me was a:
Looking at:
We see that:
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vote
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Filling in an 8x8 minesweeper grid with mines (Day 10: Double Neighbors)
The completed grid:
The solve path:
- 14.2k
1
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