supercat
• Member for 7 years, 6 months
• Last seen more than a week ago
• Illinois

2k views

An arrangement which can be readily seen to be valid albeit not minimal may be formed by observing that joining two "small" (3-matchstick) triangles and two "large" (9-matchstick) rigid triangles will ...

7k views

I believe four works. Figure that at some point one will ask Zrowag a question and get no response, so that burns a question but the only relevant permutations are the six involving the other ...

6k views

. .

2k views

What answer is "best" depends on how one defines "trivial", but if the goal is to have an answer which uses different arithmetical relationships when inverted, how about 21-9 ...

9k views

That four colors will suffice may be easily shown by the fact that four-color maps exist. That three colors will not suffice may readily be shown by pointing out particular places where it is ...

1k views

A nasty thing about liars is that when asked complex questions, they may answer in whatever fashion, other than 100% truthfulness, would be most vexing. That is a substantial complication which other ...

255 views

7S can be forcibly won with five HCP: . ♠8765432/-/♦765432/- ♠K/♥AK/♦AKQJ/♣AKQJT9 ♠Q/♥QJ/♦T98/♣8765432 . ♠AJT9/♥T98765432/-/- If West ...

1k views

How about I think that's an alternative 6+1-piece solution.

1k views

For the general case of N balloons, if it's not possible to pop all the balloons, a winning move is... If that move is unavailable... To understand why this is so... Conversely...

669 views

If passenger counts from 1 to 5 are equally distributed, it's possible to compute for each of the 343 (7x7x7) possible population distributions the expected value if one stands pat and if one takes ...

8k views

The task may be established, in a huge but bounded number of moves, by first establishing an upper bound M on the number of prisoners (possibly using Julian Rosen's approach) and repeatedly performing ...

1k views

I would guess the intended answer is that... A potentially safer approach would be...

4k views

If there are six candies on the table, the expected number of additional candies to eat will be zero. If there are five on the table, the expected number will be 5/6 of (two plus whatever the ...

3k views

If curved cuts are not permitted, it may be possible, depending upon the size and placement of the cat, to cut a regular polygon which is entirely within the circle but outside the cat, such that ...

1k views

An adaptation of r's approach, if the requirement is to, for any k, find a B such that N bits of storage can be used to allow kN/B distinct writes, is to pick B=3k, and encode the information as ...

598 views

If there is no known maximum number of switches and bulbs, the first part of the solution (finding a known upper bound) becomes much harder (refer to the other puzzle for the approach that's workable ...

5k views

A limitation of the solution given by eclipz905 is that portions of the walls would be moving away from the center. An alternative approach would be to have walls of a flexible or articulated ...

930 views

To my mind, puzzles where the goal is to formulate questions are more interesting than those which merely require finding a distribution of liars and truth-tellers that satisfies a given set of ...

24k views

How about a concave mirror, like some of the ones found in cosmetic or vanity kits? Unless one wanted to speculate that such a mirror provides views into an infinite multitude of universes that just ...

951 views

If both sides of the gorge are at the same elevation, and if the rabbit and bear collide in the middle, the rabbit's effect on the bear's momentum will be worse than if the rabbit had simply been ...

13k views

As Tanner Swett has noted, it's possible to solve the puzzle using a finite number of states beyond those of the lights themselves. His solution takes time proportional to the square of the number of ...

6k views

Assuming the doors are numbered 1, 2, and 3, ask the guard in front of door #2, "Is the sum of the number on the liar's door and the number on the door that leads to death, even". If the answer is "...

2k views

Order each robot to push a button that new robots know nothing about, but that the "get lost" robot would recognize as causing a door to slam on one's toe in a manner that would be slightly, though ...

826 views

If one is playing against an exceptionally cooperative opponent who never challenges any words, no matter how outrageous, I think the maximum would be 2449 when playing against a single opponent. ...

252 views

Instructing someone to freeze ('icy be'), or saying one is frozen ("Icy me")? If the puzzle is using cryptics, perhaps an abbreviated institution got mixed up with a yes-man (ACYOE interleaves "CO" ...

8k views

Once a bound on the number of prisoners is established, the problem may be solved in polynomial time (rather than hyper-exponential) without requiring prisoners to use an overly-complicated rule sheet,...

646 views

A solution much better than Penguino's "spiral" can be achieved by starting with Penguino's zig-zag (the one with length 5098) but adjusting it slightly. Looking at the first place the line comes ...

1k views

If the sex of each child is independently randomly determined with a 2:1 ratio favoring boys, then the stated policy will have no effect on male versus female birth rates. If, however, the events are ...

4k views

An approach which would be much more dangerous, but would be usable even if there were only one rope would to climb each rope (or the rope) and slice partway through it while leaving it strong enough ...

461 views

If the lying guard is guaranteed to be "maximally" untruthful, and the doors are labeled 1, 2, and 3, one could ask a guard to identify every number between 1 and 6, inclusive, which either identifies ...