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]
831
questions
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Self-numbers and repunits
Self-numbers or Colombian numbers (A003052 in the OEIS) are natural numbers which are not the sum of a smaller number and the sum of its digits. Repunits (in base 10) are numbers consisting only of 1'...
9
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How is the RHS related to the LHS
Please explain the following relationship:
Accessible:
2 --> 18
20 --> 48
200 --> 6
2000 --> 26
How did I arrive at these?
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votes
2
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An interesting Number sequence: 8, 10, 7, ...? [closed]
Let's see how many of you can solve this correctly
I found a number sequence puzzle somewhere in the web with interesting logic and a unique strict solution.
8, 10, 7, 12, 5, 16, 3, ?
1
vote
1
answer
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Continue the row of numbers: 1, 3, 9, 13, 65, ...?
Yesterday, I stumbled across a series of numbers that I could not solve. Maybe one of you can figure it out?
1, 3, 9, 13, 65, …?
6
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1
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Find the next number in these series..?
1, 1, 1, 1, 2, 2, 2, 2, 2, 5, 4, ?
2, 4, 6, 10, 15, 26, ?
71, 194, 38, 1701, 89, 76, ?
5303944, 6677714, 2070936216988528558, ?
1, 2, 3, 6, 9, 9, 16, 20, 18, 30, ?
You know, there is more than ...
4
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0
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+50
Given the length of sequences with different seed values, what comes next? 1, 2, 4, 5, 11, 22, etc
Edit: Apparently this site has had a few too many what comes next puzzles without anything to go off of so I've decided to make this a different albeit a bit easier puzzle.
Sequences generated by a ...
2
votes
1
answer
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1, 2, 3, 10, ... Another find-the-next-number-in-the-sequence puzzle
Can you spot the pattern and continue the following sequence?
1, 2, 3, 10, 12, 16, 25, 37, 55, 81, 100, ...
Hints:
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1
answer
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What is the next number in the sequence below [closed]
6.000,7.000,.857,8.168,.105,77.790
Which of the following responses completes the series
.001
740.857
9.524
.013
0
votes
0
answers
156
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Two number patterns (clue: or geometrical shapes)
Solve the series:
Series 1:
6 and 1
5 and 2
4 and 3
5 and 1
???
Series 2:
6 and 1
5 and 2
5 and 1
4 and 3
???
3
votes
1
answer
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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,...
6
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Same sequence interwoven with itself creating groups
If we take all the digits from 1 to 9 and lay them out in order.
123456789
Now repeat the sequence and add it to the end.
123456789123456789
Now let's copy and reverse everything to create a second ...
18
votes
1
answer
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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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2
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How Many Magic Hexagons that use repeated digits?
There exists only 1 normal magic hexagon that uses non repeating consecutive digits for 1 to 19.
If We allow digits to repeat we can create something like this hexagon that is made up using ...
2
votes
1
answer
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More bits the merrier
The computer department at Puzzled State University devised an inefficient
bit-based
(zeros and ones) number system, n',
for their ever more bit-happy machines.
...
11
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1
answer
283
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Square Sum Problem Summing 3 consecutive digits along the line
In this image from a numberphile video we see a sequence of numbers from 1 to 15 without repeats where any pair of neighbouring digits sum together to make a perfect square number.
15 is the lowest ...
3
votes
1
answer
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Smallest 3x3 Magic Square of different square sums
Consider the follow magic square highlighted in yellow. The sum of its rows and columns are in green and the sum of the diagonals in red.
All of its sums are a square number with the sum of the whole ...
3
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1
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please Extend this list of Units
Given the following list of four corresponding series of numbers, what would the fifth line look like?
1 : 1.4 / 3
2 : 3 / 2 | 1 : 2 / 6
2 : 3 / 2
1 : 2 / 3
Hint 1: This puzzle was inspired by the ...
3
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0
answers
152
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Odd one's out (sequence)
Once upon a time, there was a curious mathematician named Friedrich. One day, while exploring a new area of mathematics, he stumbled upon an intriguing sequence of numbers:
0, 1, 2, 2, 4, 3, 3, 4, 4, ...
3
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1
answer
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A Weird Sequence
Today, I was in Rome for a vacation. The most peculiar thing happened. A gnome walked up to me. Uttering no words, it handed me a slip of paper.
0, 1, 1, 2, 3, 2, 5, 5, 5, 9, 4, ?
Naturally, I was ...
2
votes
1
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Another predictable sequence: 1, 1, 2, 2, 1, 17, etc
This puzzle is part of the Monthly Topic Challenge #6: Is it really that [time] again?.
Can you find the pattern? Note: The next number hasn't been worked out yet.
...
1
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1
answer
229
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What are the missing numbers in the circle?
Given the following diagram, what are the missing two numbers in the last figure?
This is from a mathematics book for primary school
13
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1
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Twelve numbers omitted
This is the beginning of a simple sequence.
NO Computers or special knowledge are required.
Insert the missing numbers. Explain how the sequence was generated.
Note: the line breaks can be ignored, ...
59
votes
1
answer
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My dead mom left behind some number code
Background: I actually do not know the answer to this puzzle, but can answer any questions you may have. My mom who is now deceased had this series of numbers written in her notebook, that don't seem ...
10
votes
1
answer
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Will the sequence ever change?
Here is a sequence that seems to go on forever. Will it? Will this sequence ever change?
1,2,3,1,0,1,2,3,1,0,1,2,3,1,0 and so on
What does this sequence relate to?
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1
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Chinese Pinyin Puzzle
Puzzle World in VR Chat. Must Select the 8 Words in the right order 1-8. Nothing other than that I'm aware of.
3
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1
answer
276
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What is the next number in the series 1111111,111,21,13,12,11,10? [closed]
Find the next number in the series 1111111,111,21,13,12,11,10,
[There was a hint saying the answer is a single-digit integer, and the series has something to do with the number 7]
I've only been able ...
3
votes
1
answer
227
views
Two naughty programmers
The math professor wrote an equation f(x) = x and defined t as number of solutions at f(x) = 5 and u as number of solutions at f(x) = 3. He further defines N as N = t+u
Two programmers decided to edit ...
12
votes
1
answer
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views
What is the sequence?
The following 5 sequences of base-10 numbers all follow the same pattern, and converge at 14,.
What is the pattern and which number is next?
1,5,10,14,23,...
2,6,10,14,23,...
3,9,14,23,...
4,9,14,23,.....
2
votes
1
answer
339
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German number sequence
Classical format, here is a sequence of numbers, you need to find out how it continues:
5, 4, 14, 8, 0, 4, 2, 2, 2, 0, -3, -1, -2, -3, -7, -7, -6
This puzzle should also have the tag 'Germany' ...
13
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Mom Got Me Shoes For My Birthday
What number must replace the question mark below?
218
19
780
17
11
9,000
301
6
8
600
?
80
70
1
vote
0
answers
139
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An increasing decreasing sequence
In math, there are all kinds of sequences
1545, 1218, 1071, 921, 851, 832, 799, 793, 774, 745, ... is (the start of) such as sequence
What is the best number?
Note:
Even in math things change, so ...
3
votes
3
answers
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Balanced binary cycle
Let's call a binary cycle ${\bf x}:x_1,x_2,\ldots, x_{12}$ balanced if exactly 6 of the $x_i$'s are 0 and 6 of them are 1. We can place the sequence around a circle and add each two adjacent digits ...
2
votes
1
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Next number in the sequence 2, 4, 3, 10, 5, 5, 28, 11
2, 4, 3, 10, 5, 5, 28, 11, 7, 8, 82, 29, ?
I was asked this on an interview. My time ran out and I couldn't figure out the pattern. I am spotting a lot of $3^n + 1$ terms here maybe that is helpful ...
17
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1
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Radical IQ challenge
This puzzle is part of the Monthly Topic Challenge #2: IQ Puzzle Parody
Can you find out the next one in the sequence, how it's different to the ones before it, and explain the pattern?
1
10
11
20
31
...
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1
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There are a lot of gifts missing
1-108-121-128-146-157-195-227-305-315-???
There are a lot of gifts missing
There is a missing 11th number which is it?
This is not on OEIS :)
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2
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A number association puzzle
These 0 to 10 digits are associated with the specific numbers as shown below.
What are the associated numbers for digits 9 and 10? Why?
Bonus: Is there an associated number for 11?
3
votes
1
answer
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Decode 'xorarlpziebpwanywxnf' to find the hidden message
Try to find the hidden message in the text:
xorarlpziebpwanywxnf
These seemingly random numbers will help you solve the puzzle:
...
14
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1
answer
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A strange number pattern, isn't it?
This looks like a strange number sequence to me. Or is it?
1 2 3 4 5 6 7 8 9 10 12 13 14 15 16 17 18 20 21 22 23 24 25 27 28 29
30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 ? ? ? ? ?
So what are ...
0
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0
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I promise, never again! [duplicate]
The first 15 non-negative integers are written below. The 16th number contains 4 digits! - yet it is the next and the last term.
No special knowledge required. Try see if you can find a pattern and ...
2
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2
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Planar Investigator
Use logical deduction to place a different digit from 1 to 9 in each circle below so that 8 of the arrows form the primes 23, 31, 41, 53, 59, 79, 89, and 97. (We view an arrow starting at digit A and ...
2
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1
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What's the next term in this sequence?
I created this simple number sequence puzzle, I don't know if anyone used the same idea before. Find the term at the question mark in the sequence.
$$
25, 42, 56, 97, 176, 232, 251, 269, 394, 518, 572,...
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A simple number sequence puzzle
This is a simple number sequence puzzle, you are given 6 related number sequences, observe them, find the pattern; Your task is to give the first sixteen terms in the seventh sequence.
$$1d5, 2d3, ...
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Gah, these number sequences are just too boring!
Gah, these number sequences are just too boring! You just plug them in and then you're done!
There is a function $f : \mathcal{S} \to \mathbb{Z}$, where $\mathcal{S}$ is a finite subset of the ...
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1
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I can't remember her birthday!
My Persian friend said:
I will meet you in New York on my birthday.
But I can't remember her birthday! I only found this riddle related to her birthday in old chats.
$(y+z)/y = (y)/z = (A+10)/10 $
$...
18
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1
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Describe your ability to solve this number sequence!
Here is a sequence of numbers:
0, 2, 4, 6, 8, -, -, -, 10, 12
Can you fill in the three blanks and thus reveal your excellent puzzle-solving ability?
0
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1
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What is this sequence? 1, 11, 21, 22211, 33221
In this sequence:
1, 11, 21, 22211, 33221, 433332211, 44444444332221, ?
Can you guess the next number? What is this sequence?
Hint 1:
Hint 2:
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1
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How do you go from 2021 to 2022?
Below a path is shown that goes from 2020 to 2021.
Following the same path, how do you go from 2021 to 2022?
2322, 2302, 2012, 2020, 2028, 2025, 2024, 2029, 2021, ..., ..., ..., 2022
Fill the gap.
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2
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What should be the most logical and appropriate 9th term in this sequence?
Consider this sequence
3, 5, 10, 20, 39
What is the pattern? I initially thought it might be a pattern of *2-1, *2,*2,*2-1 (a group of *2-1,*2,*2 repeating itself), but don't think this is a valid ...
3
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1
answer
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Very long number sequence
Here is the sequence:
...
9
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1
answer
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Complete the rest of this seasonal sequence
Usually I don't like this kind of "guess the next terms" puzzle.
But at this time of the year I wonder whether it makes sense to post such a question.
So here is the start of a sequence:
$$...