# Questions tagged [number-sequence]

A puzzle that asks for the pattern in a given number sequence.

57 questions
Filter by
Sorted by
Tagged with
8k views

### 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
2k views

### 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 ...
349 views

### 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. ...
50k views

### 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 ...
480 views

### 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 ...
1k views

### 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 ...
3k views

### 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 ...
3k views

### 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 ...
979 views

### 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 ...
5k views

### 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, ?
4k views

### 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 ...
20k views

### 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 ...
559 views

661 views

### 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•...
339 views

### 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 ...
747 views

### What is the next integer in this sequence?

First, I offer you a little something to put you in the right spirits: For many many years, black cats have had some interesting associations and reputations, which no doubt helped inspire The Black ...
394 views

### 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 ...
377 views

### A final batch of four sequence puzzles

This is my seventh (and probably last) batch of sequence puzzles that are nasty and hard to solve; I stress that each of them has a clear and justifiable solution. Sequence 1: RC, NU, RT, RS, PI, ...
921 views

### SafeCracker #3 - We've Been Blocked [closed]

Our Last Safe To Conquer Ok, team, this one might give us a little trouble. Nothing we can't handle though... let's go... This safe model is "The NevaCrak 9000" - the most secure safe there is. ...
366 views

### Next number in the following sequence? [closed]

In following sequence, Find the next number? 85, 79, 73, 69, ?
746 views

### 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 ...
737 views

### 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, ... ...
306 views

### 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
205 views

### 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 :)
141 views

### Fill the grid - 2.0

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

### 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 ...
252 views

### 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 ...