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Questions tagged [open-ended]

NOTE: This tag is currently being debated on Meta. Questions asked under this tag may not fall under the scope of the site. Please be mindful of that when asking a question. Used when the tagged puzzle is open ended to all solvers and could be "bested" at any point, if a given solver has a better solution that fulfills the askers requirements.

13
votes
6answers
276 views

Pulling Apart a Jigsaw Puzzle

Assume you have a jigsaw puzzle that is also a tessellation. This means every piece has an identical shape and can be assembled into a 2D pattern that fills the plane with no gaps. Such a jigsaw ...
2
votes
2answers
613 views

Dreadful Dastardly Diseases, or Always Atrocious Ailments [closed]

So the other day, I was in a pharmacy and I saw that they had a "cold 'n' cough" medicine. The alliteration caught my eye, and I wondered it would be possible to create alliterative names with other ...
5
votes
12answers
3k views

Omega? Krypton? [closed]

Since today is April Fool's Day... Yes! Omega Krypton! You are spotted! This is an April Fool's Day game! Think of as many ways to change Omega to Krypton! Rules: 1. You can use numbers, letters and ...
13
votes
3answers
994 views

From jafe to El-Guest

Largely inspired by From Puzzling to StackExchange by CodeNewbie From jafe to El-Guest jafe > cafe > cate > cete > cet > get > gest > egest > e gest > e guest > el guest Rules: In any move, you ...
8
votes
2answers
263 views

Masyu puzzles with many circles

The rules of Masyu: Make a single loop with lines passing through the centers of cells, horizontally or vertically. The loop never crosses itself, branches off, or goes through the same cell ...
8
votes
2answers
504 views

Missing checkmates in one

Have you ever missed a one-move checkmate and immediately realized it after making your move? If you have, you just might have what it takes to crack this problem. Let's take an example: g4 e5 ...
17
votes
5answers
2k views

Second-rate spelling

Find the longest word which can be spelled with the second letters of a group words in alphabetical order. An example with incomprehensible (16 letters): a...
6
votes
5answers
321 views

Breaking Balance (Part A)

If we assume the classic balance puzzle (Twelve balls and a scale) is phrased like this: You have 12 coins that are identical except for one counterfeit that is heavier or lighter. Can you use a ...
15
votes
0answers
655 views

Peaceful Encampments

This math puzzle is due to Donald Knuth (as far as I know; maybe he got it from someone else) circa 2014. Consider a plain represented by the unit square. On this plain we want to “peacefully ...
11
votes
3answers
337 views

You may remove pieces of your opponent's!

You are in a regular chess tournament, your opponent is Deepest Blue AI who considers every kind of possibilities and does not make any mistakes. But you are given an opportunity to remove any pieces ...
4
votes
1answer
122 views

What's the most triangles you can make with 4, 5 or 6 straight lines?

All the triangles can stick together. The triangles counted is the independent triangles, triangles made up of two shapes, a triangle made up from 3 shapes, or the outline of the shape consisting of 4,...
0
votes
1answer
114 views

Need help to decipher this encrypted text

I am relatively new to deciphering texts and I have the following ciphertext: xbt ufp ekyzkikn dt nkojvhk? e ndmr jfo nggv du kwjt gun pjv. I tried Caesar Cipher but to no avail. It would be ...
3
votes
3answers
1k views

Three coins for the fair king [duplicate]

Based on the question Eight coins for the fair king: I saw a comment saying "There isn't a good solution known even with three coins in all cases". So the challenge here is to try to solve the same ...
2
votes
2answers
163 views

Heaven or Hell? [closed]

To decide whether you go to heaven or hell, your life is put on the balance. All depends on which way it tips. John dies and waits in line to have his life weighed. Eventually he reaches St Peter who ...
2
votes
1answer
132 views

A construction toy for children [closed]

Alice has an idea for a construction toy made from plastic. Each building block is in the shape of an uppercase letter of the alphabet. No other characters are to be used. Children will ...
1
vote
1answer
127 views

Wicked Winding Words!

What is the highest number $n$ of $n$-letter words can you find that share this property? i.e. highest number $n$ that you can find (not found on any other sites). I will accept the answer with the ...
5
votes
1answer
489 views

What is the longest word that can be made out of all the scrabble tiles?

What is the longest word that can be made out of all the Scrabble tiles? If you didn’t know, there are 100 tiles when you play Scrabble. I was wondering what was the longest word you could make out ...
5
votes
3answers
222 views

Moans to Rocky in 4 moves?

In his novel A Case of Need, one of Michael Crichton's characters claims that the classic word‑ladder‡ "MOANS to ROCKY" can be made in 4 moves (5 lines total). But the book does not ...
18
votes
4answers
3k views

A Tic-Tac-Toe type game

I found this interesting game with no name: You have a 1x11 grid, like this. The way you play is similar to Tic-Tac-Toe (aka Noughts and Crosses). Players take turns to place Xs and Os on the grid, ...
3
votes
3answers
455 views

Make a sentence with the most different uses of the same word [closed]

Background I recently stumbled across the following grammatically correct sentence: Buffalo buffalo Buffalo buffalo buffalo buffalo Buffalo buffalo. This sentence relies on the fact that the ...
2
votes
2answers
257 views

Longest autological loop?

A word is said to be autological if it describes itself. This can be a property of both nouns and adjectives; for example, "noun" is a noun and "pentasyllabic" is pentasyllabic. We can also construct ...
3
votes
3answers
338 views

Make me a room-filling pattern!

So I need a new knitting pattern, but I figured this might be a nice puzzle. I'm looking for a pixelated 2D-shape that can be used in a room-filling pattern (rotation and flipping allowed). The ...
5
votes
2answers
381 views

Improve my 3D puzzle

3D View of one solutions http://autode.sk/2Dg4FWx I designed a 4x4x4 soma cube in AutoCad and then built it with wood cubes. There are twelve pentacubes and one tetracubes. Each piece is unique and ...
6
votes
3answers
479 views

Place three Knights, three Bishops and three Rooks on this board snippet

Place three Knights, three Bishops and three Rooks on this board snippet. The only rule: each piece has to be attacked exactly once. Notes: Ignore color, so every piece attacks every other piece ...
9
votes
2answers
267 views

Create a 1 meter measure

How many folding steps do you need to create a $1 \, \text{m}$ measure from an ideal DIN A0 sheet? This sounds easy, but consider that this paper has edge lengths of $\sqrt[4]{2} \, \text{m}$ and $\...
10
votes
1answer
452 views

Conway's Siege of Life

They are immortal and they are killing us. We may not be able to kill them, but we might be able to keep them occupied, distracted, for eternity. But we need to figure out how. Before there are no ...
27
votes
18answers
16k views

Don't settle for a billion [duplicate]

While Artur is willing to settle for a billion, I'd like a much bigger return on my two matchstick investment. Moving only two matchsticks, what is the largest number that can be created from the ...
5
votes
3answers
474 views

English word with most valid substrings

What English word has the most valid word substrings, no repeats? Examples (I may have missed some words): AIRSPACES: a, i, air, spa, space, spaces, pace, paces, ace, aces DEMONETIZED: demo, demon, ...
10
votes
11answers
12k views

Infinitely long loaf of Bread [closed]

You are visiting your old friend Mike at Infinitely's Baking Shop. Just as you arrived, he was taking out a fresh, infinitely long loaf of bread. Both of its ends extend infinitely long in a ...
6
votes
4answers
420 views

Constructing 0.35 Unit Length

The Problem The medieval equivalent of Bob the Builder has a new job offer: He is to build a box with the measures of $0.35$ units by $0.35$ units by $0.35$ units for a king. There is a little ...
6
votes
1answer
411 views

Picture a graph without words

You may have played/sung/heard a song without words in concert, in choir, and in a Sushi restaurant. Who hasn’t?! Well here is a picture without words, only axes: And here it is without JPG-...
4
votes
3answers
363 views

Find the most MissSpellable word, but in a good way?

Most MissSpellable Word - English? I'm not a native English speaker but I tend to keep an eye on my spelling and grammar. I recently misspelled "throw" as "throe", which, to my surprise, was a real ...
12
votes
2answers
890 views

How many consecutive integers can you make using only four digits?

In the spirit of the classic four fours, I wonder what's the optimal set of four numbers? Your goal is to make the most consecutive integers using four digits of your choice. Pick four: $0,1,2,3,...
5
votes
4answers
750 views

Challenge : Create a star shaped crosswords (Smaller numbers of distinct letters wins !)

Rules: Create a star-shaped crossword using 6 letters English words. Clues for the crossword is not needed. Use common English words. Direction for diagonals is TOP to DOWN. Direction for Horizontal ...
22
votes
13answers
7k views

Playing “Guess a Number” with myself

I want to play a game where one person thinks of a number and the other tries to guess it, but I want to play this game by myself. The puzzle is to come up with a way to play this game. Rules (have ...
12
votes
1answer
485 views

Forced checkmate in n

I assume most people on PSE know a bit of chess With white to move, this is checkmate (1. Qb7#): That's boring. Let's try something more interesting. With black to move, black can FORCE white to ...
-6
votes
1answer
244 views

Any twelve year-old can answer this question

Come up with a question between five and ten words long with an answer that contains more than three times as many unique words as the question, does not contain any of the question words, and does ...
3
votes
1answer
450 views

Infinitely simple polygon solipsism

           Solipsism — The self is all that can be known to exist. Above is a simple polygonal region divided into infinitely many different-...
9
votes
3answers
361 views

Unreflected infinitely simple polygon reflexivity

(This was retrofitted to more tightly match a surprise solution and to allow for another puzzle with the original intent.)                   &...
10
votes
4answers
721 views

Prime Circuit Optimisation

It's logic gates time! You are only allowed to use NOT, OR, AND, XOR gates, accepting 1,2,2,2 inputs respectively. PART ONE You must build a circuit with $n$ inputs, and 1 output. The output must be ...
6
votes
1answer
253 views

She Lia Squared: Our daughter asked, “How many words can it make?”

For puzzle experts out there I'm certain this will seem trivial. Our daughter recently conned my wife and I into purchasing interlocking foam squares for her bedroom floor. On each square is a ...
7
votes
1answer
428 views

Character Navigation

Consider the following grid of streets with roadblocks: If you are facing in the direction of the arrow and want to get to the dot, the highlighted path is the shortest: This traces out an L. Let'...
4
votes
1answer
232 views

The Autonumerigram Challenge [duplicate]

Some phrases both refer to a number, n, and are comprised of n alphabetic characters. I call any such phrase an autonumerigram. For example, four has 4 letters seven plus seven has 14 letters ...
12
votes
2answers
526 views

KenKen Zen: A journey begins

Let us shy away from the materialistic opulence of 361- cell KenKen layouts (−9 to +9, squared).  Let us contemplate a modest KenKen journey, unburdened by gratuitously ...
7
votes
3answers
493 views

Building the ideal Scrabble dice set

This is a genuine question and I don't know the "correct" answer to this. I'm also of two minds if it is really on-topic on the site. Finding the answer is surely "a puzzle" (if possible), but it ...
4
votes
1answer
268 views

A Stranger (Chess Sliding Puzzle)

A suspicious stranger lurks in the village. Deal with him before escorting the King to the luxurious safety of h8. White is first to move. Only legal chess moves are allowed. Pawns are not promoted ...
14
votes
3answers
359 views

Pool of Pawns (Chess Sliding Puzzle)

The King has tired of watching the Queen swim in the Pool of Pawns. Help him return to his palace on h8 using as few moves as possible. Only legal chess moves are allowed. Pawns are not promoted on ...
27
votes
3answers
886 views

Rook River (Chess Sliding Puzzle)

The absent-minded king has gotten himself lost. Help him return to his palace on h8 using as few moves as possible. Only legal chess moves are allowed. Pawns are not promoted on the final rank. You ...
5
votes
1answer
249 views

Can You Find a Tower of Hanoi Word?

Consider a simple Tower of Hanoi set consisting of three rods and three disks. This tower has an optimal solution of seven moves; these seven moves are the only ones allowed in what follows. For the ...
22
votes
9answers
3k views

Longest “De Bruijn phrase” in English

Let's call De Bruijn n-phrase a sequence $S$ of n words $W_1 W_2 W_3... W_n$ such that any "left-rotation" of its words constitutes a correct and meaningful phrase. The left-rotations of $S$ are: $...