# Questions tagged [open-ended]

OPEN-ENDED PUZZLES ARE NO LONGER IN SCOPE. Used when no answer can be guaranteed to be the last, best one. If a puzzle instead has a provably optimal solution, tag with [optimization].

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### Making π from 1 2 3 4 5 6 7 8 9 [closed]

There have been two other questions here and here that are similar to this one, but this changes the rules up a little. Your job is to approximate $\pi$ using the sequence of digits (in order): 1 2 3 ...
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### Growing anagrams - What is the longest possible list forming a sentence? [closed]

This is a challenge for word-puzzle lovers. It might be a bit more of a game than a puzzle, but I think it is not limitless in it's answers, so a final answer could be found (eventually). What is the ...
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### The Longest Word Made from Chemical Symbols [closed]

So, as you probably know, each and every element in the Periodic Table has its own unique chemical symbol, which is either one, two, or three letters long. For instance, Oxygen is represented as O and ...
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### 3:3! It's a football score! [closed]

Given to me, by a friend: How would you make 20, using two threes? You may use any basic operation. And others, such as square roots (the symbol), factorials, etc. Any operation is allowed. Just ...
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### The most words that can be made by successively adding one letter to the original word? [closed]

What is the largest number of words that can be made by just adding one letter to the original word, where each iteration is a meaningful word? E.g. ...
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### 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 ...
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### A rhopalic sentence of at-least 5 words, beginning with as long word as possible [closed]

Rhopalic sentences are sentences which have words whose length is one more than the previous word. eg: I do not hunt birds. I do not know where family doctors acquired illegibly perplexing ...
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### Forced selfmate in n-moves [closed]

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 ...
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### Shortest sentence with two auto-antonyms [closed]

You have to use two words that are each their own opposite (auto-antonyms, contronyms, contranyms or whatever you want to call it) in the same sentence. This means that each of the two words in used ...
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### From jafe to El-Guest [closed]

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 ...
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### Can you solve those laser puzzles? (puzzles created by the community) [closed]

So, I was bored and I made a small game for this site! In this game the user who solves the previous puzzle gets to create the next one and they will always be more complex. Website link and string ...
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### Four fours to get $\pi$ [closed]

Four fours is a famous puzzle (made trivial with logarithms). For this puzzle, we take inspiration from Glen O's challenge from a few years back. The rules here are slightly different, but the goal is ...
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### 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 ...
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### Longest sentence with each letter repeated n times [closed]

Inspiration: This question was inspired by Word sets with no repeating letters Rules: Sentences can be of any length. Every letter used in this sentence, must be used n times. n can be any number. ...
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### Longest sentence where all words are anagrams of each other [closed]

Won, now own. Rules: A “word” is an entry on dictionary.com. A “sentence” is any text that is grammatically correct, has a complete meaning in the English language, starts with a capital letter and ...
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### Longest arithmetic expression where the answer is equal to the number of letters [closed]

You can use any mathematical operations represented by English words. These English words must be found in a commonly used dictionary. Spaces are neither letters nor words. You can not use the same ...
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### Knight on the keyboard [closed]

You are given a QWERTY keyboard, and are allowed to choose where you wish to start. You are only able type in the same way a knight is able to move on a chessboard (but in this case, on the keyboard). ...
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### 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 ...
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### Bouncing Robots: Graphical Puzzle [closed]

Robots are indicated by the arrowhead shapes and the labels "r", "y", "b", "g". The label obviously corresponds to their color. The aim of the puzzle is to pick up the shapes and put them down in the ...
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### One syllable words with many vowel sounds [closed]

I'm not entirely sure how to word this, but what is the largest set of one syllable words you can find in which every phonetic sound is the same except the vowel? For example, 'arc', 'orc', and 'irk' ...
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### 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 ...
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### The Longest Word Made from Specific Chemical Symbols [closed]

So, my first question on this topic was answered fairly quickly with quite a long word, so I thought I might post a different version of the puzzle The idea this time is similar to last time: you ...
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### What is the Sparsest Word? [closed]

Side note: If you know a better way to describe an anagram that doesn't use all the letters except for "words within the word" or some other lengthy phrase, please let me know. I considered asking ...
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In the US, text painted on roads reads bottom to top: AHEAD STOP In the UK, it reads like normal text: NO ENTRY ...
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### Highest possible score my friend could earn in one Scrabble turn? [closed]

My friend has a great vocabulary but is also quote humble. Every time we play Scrabble he wins easily. He says he tries his best, with one exception: If the opportunity ever arose, he would never ...
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### Magic-the-Gathering Challenge: Cheapest Legacy Turn 1 kill [closed]

Your Goal: Win the game turn 1 with you beginning the game (so not on the draw) using the cheapest price total of cards used. Rules: Use the "Price Trend" price from http://www.magiccardmarket.eu ...
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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'...
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### MathJax: ones and zeros

Do or do not, there is no try.     — Yoda Here is another MathJax puzzle. The Starring MathJax puzzle involved handling numbers in MathJax, even though there are no count registers or ...
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### She Lia Squared: Our daughter asked, “How many words can it make?”

Our daughter recently conned my wife and I into purchasing interlocking foam squares for her bedroom floor. On each square is a different letter of the alphabet. To cover her entire floor we had to ...
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### Starring MathJax

Twinkle, Twinkle, little star... Having enjoyed @Humn's recent MathJax puzzles (MathJax exposed and MathJax re-flex), I decided to contribute some of my own. This one is a classic $\rm\TeX$ exercise,...
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### Find the longest string of words such that the (4 letter) end of one word is the start of the next [closed]

Here is an open-ended challenge. Find the longest series of English words such that the final four letters of word $n$ are the same as the first four letters of word $n+1$. Example (3 words) ...
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### Challenge: Longest x-height word/sentence [closed]

A common puzzle is to see how to make sentences from the same letters, or the longest word in alphabetical order, etc. see here for a list. Now 'the x-height or corpus size refers to the distance ...
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### 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 ...
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### What is the smallest positive number on an 8-segment array? (no repeats) [closed]

You are provided with the 8-segment array in the picture together with all the necessary electronics to make any combination of lit segments you want. Fillable version for graphics. https://i.sstatic....
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### Longest Word without repeating character-pairs [closed]

What's the longest English word that doesn't contain the same two letters in a row more than once? Good word : too contains to ...
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### Challenge : Create a star shaped crosswords (Smaller numbers of distinct letters wins !) [closed]

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 ...
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