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
4
votes
1
answer
213
views
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'...
- 16.7k
9
votes
1
answer
867
views
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?
- 4,011
-5
votes
2
answers
119
views
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
141
views
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, …?
- 19
6
votes
1
answer
268
views
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 ...
- 631
4
votes
0
answers
753
views
+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 ...
- 669
2
votes
1
answer
282
views
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:
- 1,199
-2
votes
1
answer
153
views
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
views
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
???
- 141
3
votes
1
answer
296
views
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,...
- 16.7k
6
votes
1
answer
258
views
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 ...
- 591
18
votes
1
answer
702
views
What is the last integer in this sequence?
Here are the first several entries in a finite sequence of integers.
$$ 31, 45, 71, 89, 91, 94, 111, 112, 118, 121, 126, 131, $$
$$ 134, 135, 139, 143, 144, 145, 148, 158, 161, 189, 193, 194, \dots $$
...
- 41.4k
1
vote
2
answers
162
views
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 ...
- 591
2
votes
1
answer
175
views
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.
...
- 21.8k
11
votes
1
answer
283
views
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 ...
- 591
3
votes
1
answer
191
views
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 ...
- 591
3
votes
1
answer
401
views
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
votes
0
answers
152
views
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, ...
- 31
3
votes
1
answer
196
views
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 ...
- 133
2
votes
1
answer
379
views
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.
...
- 2,599
1
vote
1
answer
229
views
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
- 111
13
votes
1
answer
886
views
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, ...
- 20.7k
59
votes
1
answer
56k
views
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 ...
- 403
10
votes
1
answer
909
views
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?
- 4,011
-4
votes
1
answer
248
views
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
votes
1
answer
276
views
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 ...
- 35
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 ...
- 1,270
12
votes
1
answer
717
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,.....
- 1,005
2
votes
1
answer
339
views
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' ...
- 1,103
13
votes
1
answer
2k
views
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
- 17.5k
1
vote
0
answers
139
views
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 ...
- 6,935
3
votes
3
answers
182
views
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 ...
- 131
2
votes
1
answer
218
views
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 ...
- 123
17
votes
1
answer
4k
views
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
...
- 2,459
5
votes
1
answer
297
views
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 :)
- 5,971
8
votes
2
answers
588
views
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?
- 4,011
3
votes
1
answer
1k
views
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:
...
- 141
14
votes
1
answer
2k
views
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 ...
- 39k
0
votes
0
answers
72
views
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 ...
- 23.7k
2
votes
2
answers
229
views
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 ...
- 15.3k
2
votes
1
answer
261
views
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.
$$
25, 42, 56, 97, 176, 232, 251, 269, 394, 518, 572,...
user78980
0
votes
1
answer
178
views
A simple number sequence puzzle
This is a simple number sequence puzzle, you are given 6 related number sequences, observe them, find the pattern; Your task is to give the first sixteen terms in the seventh sequence.
$$1d5, 2d3, ...
user78980
11
votes
1
answer
332
views
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 ...
- 815
8
votes
1
answer
962
views
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 $
$...
- 976
18
votes
1
answer
1k
views
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?
- 8,069
0
votes
1
answer
359
views
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:
- 135
7
votes
1
answer
237
views
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.
- 25.1k
0
votes
2
answers
208
views
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 ...
- 101
3
votes
1
answer
126
views
9
votes
1
answer
400
views
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:
$$...
- 7,229