# Questions tagged [number-sequence]

A puzzle in which the hidden pattern behind a given sequence of numbers (and, often, the next term) is to be found. Use with [sequence]

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### Interview Question or Pathbreaking puzzle

I thought this changes the way series of numbers are looked at 1 1 1 2 1 1 2 1 1 Write down the next three lines
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### Four is Cosmic!

This is a little puzzle I heard a while back from one of my mathematically inclined friends- I get the sense that it's bounced around a little, so forgive me if you've heard it. There is a sort of ...
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### Number sequences: 6X000X9, 700XX08,00000015,?,00000015

Here is the question: 6X000X9，700XX08，00000015，？，00000015，？，00000015 This question actually comes from the puzzles made by my friend. He gave me his puzzles recently but I couldn't figure it out. ...
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### Missing number in this sequence?

I heard this puzzle in a quiz I participated in: 10, 11, 12, 13, 14, 15, 16, 17, 20, 22, 24, ?, 100, 121, 10000 What is the missing number? (You don't need to do any big calculations, and you don't ...
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### Two honeycomb hints (yet another 'find the next number in the sequence')

Find the next number in the sequence $1,7,74,\dots$ First hint: Second hint: To clarify: the 'hints' are really clues. They are hidden, because any of the two alone could be enough to solve the ...
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### Fill the holes? [closed]

You have to fill the boxes to make the equation true:   +   +   = 30 Using only 1, 3, 5, 7, 9, 11, 13, 15. You can also repeat the numbers. (eg: 1 + 1 + 1) Edit1: the boxes of the equation are empty ...
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### What is the next number and why? - 11,21,1112,… [duplicate]

Simple logic question, what is the next number and why? 11, 21, 1112, 3112, 211213, 312213, 212223, 114213, ?
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### Mysterious message from the NoSlaves™ Calculator Co

So my son is starting to show an interest in mathematics, and being the awesome dad that I am, I decided to buy him a basic calculator. Being the cheapskate that I am, I ordered the cheapest one I ...
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### What is the next number? 24,54,90,120,168,210,240,288,360,440 [closed]

Question : What is the next number in the following sequence? (not finite) $$\large24,54,90,120,168,210,240,288,360,440,\dots$$ My Solution I'm trying a closed form solution I tried computing the ...
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### Complete the number-sequence

2 → 6 3 → 12 4 → 20 5 → 30 6 → 42 9 → ? Can you find a correspondence between these numbers? It's not mine, so I don't take any credit. I've just seen it in Linkedin and wanted to share with ...
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### What is this magic trick with 6 cards featuring numbers between 1 and 60?

I hope this is on topic. I have a set of kids' magic tricks but I have lost the instructions! I was hoping this might be a good place to get some help. Here is the first one. What is the trick and ...
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### Very simple, yet unsolved, sequence of numbers

A simple sequence of numbers, which I encountered during intermediate school, in my math book. Any person that finished intermediate school possesses the necessary toolbox required to solve this ...
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### A Sequence That Keeps Changing?

So I get this special sequence of "items" as the following: 2 1 3 4 7 8 2 5 2 3 9 But look! If I put some numbers (randomly) in front of the sequence: 3 4 2 1 3 4 7 8 2 5 2 3 8 And yeah! ...
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### What is the next number in this sequence? 0, 1, 11.2, 10.2, 113.2, 103, 103.2, 0.2, 1.2, 2.2, 2, …

0, 1, 11.2, 10.2, 113.2, 103, 103.2, 0.2, 1.2, 2.2, 2, ? The only hint I'll give at this stage is that the sequence is infinite. If nobody gets it within a few days, I'll give a few terms that come ...
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### Introducing S-sequences: which is the shortest to contain all integers 1 to 20?

Consider a sequence (finite or infinite) of different positive integers, such as the following, in which the first term is 1, and thereafter the nth term is either the previous term plus n, minus n, ...
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### Cryptobiology? Biocryptology?

I have a friend who is a self-proclaimed cryptobiologist. Okay, maybe I don't, but if I did, I like to think she would have presented me with this puzzle: Find the hidden message: 441344•...
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### Numbers in the series: The British way

What are the next two numbers in series? Six hundred and forty Five thousand Eight thousand ? ? What are the next two numbers? Is this a trick question? Note: I am using ...
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### A Game Of Cat And Mouse: Part 2

Part 1 can be found here. Information from Part 1 is not required to solve this puzzle. Having identified where El Gato intends to strike next, you charter one of the Bureau's jets and fly off to ...
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### Sequence seen on the street

I was walking on the street when I saw the following numbers: $0, 7, 2, 3, 9$ The sequence continued a bit further then looped back. However, it was not the sequence I was expecting, so it took me ...
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### A sequence about you (Puzzling Stack Exchange users)

I have a mysterious sequence for you... $204, 186, 172, 133, 126, 123, 120, 119, 111, 107, 102, 96, 90, 87, 86, 86, 85, 79, 75, 73, 70, 68, 66, 66, 65, 65, 65, 64, 64, 64, ...$ This sequence may ...
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### A sequence defined by a single fraction

I have a sequence of numbers here, which follow a very simple rule that can be expressed using a single fraction: 1, 2, 10, 11, 13, 15, 20, 22, 25, 28, ... What is this rule (in particular, what ...
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### IX-NAY on the IX-SAY

Will this sequence ever have a 6 in it? 9, 1, 1, 1, 10, 3, 1, 1, 10, 5, 1, 1, 10, 1, 5, 2, 1, 1, 10, 1, 1, 1, 5, 4, 1, 1, 10, 3, 1, 1, 5, 1, 1, 1, 5, 2, 1, 1, 10, 5, 1, 1, 5, 3, 1, 1, 5, 4, 1, ... ...
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### Fill The grid - 3.0

Can you fill this grid ? Version ($\pi$) In text: ?14516 243748 120581 17186? 01?857 HINT 1 HINT 2 HINT 3
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### An ad-hoc number sequence to solve

Inspired by another question here, I thought I might create my own: Fill in the correct number in this sequence: 5, 3, 4, 9, 8, 3, 5, ... And of course, explain why :)
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### Next number sequence

Be forewarned: this is a riddle in the spirit of riddles. Given the following: ...4522222222255555555599999999 What are the next digits? Note: I did not specify the number of digits you should ...
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### The "Slightly Spooky Sequence" Game

Two players, Alice and Beatrice, having previously agreed on a positive integer N (say 30) as a limit, take turns to write a sequence of positive integers. In the first turn Alice writes 1. Thereafter,...
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### The Generic Number Sequence Puzzle

If you are in a hurry, you can skip the story below, there's a TL;DR near the end. The gist is that we are going to solve every number-sequence puzzle ever*, all in one go. *: Terms and ...
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### Yet another batch of four sequence puzzles

This is my sixth batch of sequence puzzles that are nasty and hard to solve; yet, each of them has a clear and justifiable solution. Sequence 1: Ca, Cl, ??, Er, ??, Po, Te, Th, ?? Sequence ...
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### A simple but most devious sequence puzzle

This is a question from a previous, now-defunct version of the Temple of Quetzalcoatl, that I've posted here as an exemplar of one of the difficult puzzles you might encounter while solving it. The ...
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### Not the usual "8 5 4 9 1 7 6 3 2 0" sequence puzzle

This is not the usual $8, 5, 4, 9, 1, 7, 6, 3, 2, 0$ sequence puzzle, which the answer of the pattern is The sequence is: $3, 9, 1, 5, 7, 0, 2, 4, 8, 6$. Can you figure the pattern of this sequence?
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### Number Sequence Series-Question 2

I want to share a question that is created by myself. I will give a hint in 24 hours and my answer in 3 days given that nobody could answer my question. Here is my number sequence: 1441,2882,5764,?,...
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### Fill the grid - 2.0

Can you fill this grid ? (Version 2.0 ) Text version 714523 191303 165088 213443 573211 91?12?
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