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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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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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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Two missing numbers
Two numbers go at the $?$s, what are they and why?
$733,\space \space 716,\space \space 645,\space \space 565,\space \space 324,\space \space 276,\space \space 77,\space \space 75,\space \space 64,\...
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A tricky batch of four number sequences
What are the next few numbers in each of these integer sequences? Each of them has a clear and justifiable solution.
1, 2, 3, 5, 8, 9, 12, 20, 21, 22, ??, ??, ...
50, 49, 48, 46, 45, 44, 43, 38, ..., ...
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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 ...
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Seeing the forest for the trees and all that jazz
No math involved here, just a bit of lateral thinking. Can you figure out what comes next?
2, 4, 8, 4, 4, 1, 3, 2, 7, 8, 3, 3, 6, 3, 4, 5...
Bonus: How about here?
6, 3, 6, 3, 3, 5, 3, 3, 4...
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What happened to the Fibonacci sequence?
I'm sure you've seen some of these numbers before:
1 3 8 13 21 30 36 45 54 63
Whats the next number in the sequence? And what have I done to the Fibonacci ...
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What is the missing number and pattern in this sequence?
The puzzle has already been solved but you can still try it just for fun without looking at the posted correct answer.
What is the missing number in the following sequence?:
0, 4, 10, 32, ?, 317 .....
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Oh dear, oh my, how blatant
Looking at the Puzzling Stack Exchange recently, I found a surfeit of number sequence riddles that all look the same! I mean, there's no difference between any of them. I'm sick and tired of all these ...
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What is the last integer in this sequence?
Here are the first several entries in a finite sequence of integers.
$$ 31, 45, 71, 89, 91, 94, 111, 112, 118, 121, 126, 131, $$
$$ 134, 135, 139, 143, 144, 145, 148, 158, 161, 189, 193, 194, \dots $$
...
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16 number puzzles on a blackboard
I have left you some number puzzles on the blackboard. Solve them and let me know what they spell.
Hint:
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Logically linked numbers
The left and right numbers are linked. What should the last number on the right be, and why?
\begin{align}
135759&: 1 \\
151364&: 4 \\
255075&: 9 \\
279422&: 36 \\
292620&: 91 \\
...
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Important days in history... and to come!
The other day I decided I wanted to come up with another simple puzzle before releasing another toughy on puzzling.SE. I came across an interesting series of dates that I wanted to share and see if ...
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Should the angels play their game?
Two angels in heaven want to play a game. One of them comes up with an arbitrary, computable function from the integers to the integers. The other angel has to guess what it is. The second angel can ...
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Number-sequence puzzle where the number goes down in the middle
My friend asked me for help with an IQ test and after she did it online she came back at me with the ones she couldn't solve.
Two of them however, I discovered are the same puzzle type, but no ...
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Can you generate the next number in this integer series and describe the rule?
2,
3,
5,
7,
...
11,
13,
17,
...
25,
29,
...
35,
...
43,
47,
49,
...
53,
59,
61,
65,
67,
...
71,
...
??
The answer (indicated by two question marks) has two digits.
When you see '...', it means that ...
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Find the next number in this sequence
Find the next number in the sequence :
1; 5; 33; 25; 2; 16; 14; 12; 11; ?
What is the next number and why ?
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Really, really, really hard sequence
... in which you have nothing to do with math
... except maybe with some counting and this and that
... but no calculations, no, definitely no.
$1, 0, 8, 62, 90, 68, 83, 89, 88, 057, 619, 028, 693,...
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Three different, and somewhat difficult, sequence puzzles
Here are three different letter/number sequences. Try to solve as many as possible. The spoilers give hints to each sequence in the form of how many elements are in the corresponding sequence.
...
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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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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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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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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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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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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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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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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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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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Number Sequence Series-Question 7
This is a series of questions that are created by me.
Here is question 7:
(23)，(55)，(155)，(1255)，？，？，(56139611)
I will give a hint to you guys in one month if nobody can solve it.
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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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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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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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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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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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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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Two honeycomb hints, part two (find the next number)
Another variant of my previous question, this one might be easier (or harder).
What is the next number in the sequence $1, 2,6, 16, ...$?
To clarify: the 'hints' are really clues. They are hidden, ...
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