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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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5 votes
2 answers
113 views

4,4,2,6,2,10,4,_ sequence from 4th grade packet

The sequence (from my child's "for fun" challenge packet, not for credit or graded) is: 4,4,2,6,2,10,4,_ The possible answers are: A) 15 B) 20 C) 25 D) 28
3 votes
1 answer
273 views

The mystery of 107 numbers

Find the algorithm that was used to create the following sequence of numbers: BAH BAA BBA BAD BBD BAG BBG BAJ BBJ BBC BCC BBF BCF BBI BCI BCB BDB BCE BDE BCH BDH BDA BEA BDD BED BDG BEG BDJ BEJ BEC ...
4 votes
1 answer
883 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:
2 votes
2 answers
895 views

2759, 4248, 1152,?

What comes next? 2759, 4248, 1152, ? What is the pattern? The op got it from this site: https://free.ultimaiq.net/nse.htm
4 votes
1 answer
257 views

mathematical magic trick

Here’s a conversation that took place between two students. A: Hey, want to see a magic trick? B: Sure, how does it go? A: Think of any number. Any nonnegative integer, I should say. B: Okay. A: ...
4 votes
1 answer
684 views

Few enigmatic puzzles [closed]

?, 63264, 12825, 65121, 02420, 48409 REDYPS, Y = ? 8, 33, 5 : X, II, ? Gods in space (7 letters) = 51151 = 8812, 22334 = 8459, 99111 = 2110910, 27772 = ?
4 votes
1 answer
745 views

Numbers turned into a number turned into numbers (start with the smallest)

What number should replace the question mark? Explain why. Hint 1
4 votes
2 answers
193 views

Strings of Kind Numbers

A positive integer is said to be “kind" if it is divisible by one of its digits other than 1 (https://oeis.org/A185186). A kind string of numbers is a finite sequence of numbers all of whose ...
5 votes
1 answer
257 views

Simple number sequence puzzle

Complete the sequence: 8, 6, 7, 3, 6, 5, 4, 5, 5, 2, ?
11 votes
1 answer
565 views

List Roman numerals to minimize total distance

This is based on a discussion with @mousetail. List the numbers from 1-100 in Roman numerals in the order that minimizes the total sum of the Levenshtein distances between consecutive numbers.
0 votes
1 answer
134 views

Relation Between The Year And The Day

Today is January 22, the 22nd day of the year 2024. I chose today because 22 is my favorite number. Now for the problem. Try to relate 22 to 2024 using math. For example, 58 is related to 271 because ...
10 votes
1 answer
1k views

What is the earliest 2024 can appear in an S-sequence?

A Sloane Sequence (or S-sequence) is any sequence of different positive integers begining with 1 in which the nth term (after the first) is the previous term plus n, times n, minus n, or divided by n ...
12 votes
2 answers
639 views

Arithmetic-progression-free sequences

This question Sudokus with no 3-term arithmetic progressions within made me wonder about the following question. What is the longest sequence composed of the integers 1..N (or 0..N-1 if you have a ...
-1 votes
1 answer
164 views

icosahedral net [closed]

The net of $20$ triangles shown to the right can be folded to form a regular icosahedron. Inside each of the triangular faces, write a number from $1$ to $20$ with each number used exactly once. Any ...
6 votes
1 answer
952 views

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 ...
10 votes
3 answers
21k views

Numbers on a dartboard - we know why they are in that order but how was it calculated without computers?

The arrangement of the numbers around the circumference of a standard dart board is as shown below 20 1 18 4 13 6 10 15 2 17 3 19 7 16 8 11 14 9 12 5 ...
2 votes
0 answers
303 views

What's the missing number related to primes?

I would like to draw your attention to this mathematical sequence related to prime numbers I've created and ask what the missing number is. 2, 5, 27, 182, 2310, 27200, ______, 8998400, 223092870, ...
2 votes
1 answer
308 views

Number sequence puzzle: strings of 0s and 1s

How can I solve this sequence? 011010, 100010, 100010, 100010, 000010, ?, 100010 https://free.ultimaiq.net/nse.htm
1 vote
1 answer
350 views

Two number sequence puzzles

123456, ?, 32407290, 128028806480 122540, 577697, ?, ? Both puzzles are from - https://free.ultimaiq.net/nse.htm
1 vote
2 answers
275 views

Numeric progressive matrix: 2-7-5, 2-3-4, 10-21-?

This is an interesting question that I got from an IQ interview test. This can have multiple answers but need a good explanation.
8 votes
1 answer
524 views

Find the pattern of the sequence of prime numbers 17 23 5 1013 2027 13

A friend gave me a sequence of prime numbers 17 23 5 1013 2027 13 and said that they have a pattern. I tried to find something but I am stumped by the fact that the numbers first increase, then kill, ...
8 votes
2 answers
843 views

A very presentable number sequence

(The title holds a clue) 12,22,30,36,40,42,42,40… Here is a finite sequence. Can you tell me the sum of all of its numbers?
5 votes
1 answer
305 views

What are the next 3 terms: 19, 43, 59, ...?

What are the next 3 terms in the following finite sequence? 19, 43, 59, 23, 79, 83, 109, 463, 569, 263, ?, ?, ?
34 votes
1 answer
1k views

A number sequence in disguise

What number should replace the question mark? Explain why. ...
-1 votes
1 answer
130 views

Numbers given: 2, 3, 6, 15, choice of answers: 24, 25, 36, 64? [closed]

Math question, numbers are 2. 3. 6. 15 Choice of answers given are A.24 B.25 C.36 D.64 What is the correct choice please?
3 votes
1 answer
380 views

Find the correct pattern in this series

My uncle send me a puzzle, and neither of us can solve it. The series seems to have an obvious pattern, however the given answers do not include that pattern. -2, 4, -6, 8, -10, 12, ..., ... a) 39, ...
0 votes
1 answer
186 views

Find the wrong number in the given series

I found this question in an Indian Highschool Reasoning Olympiad. I tried looking for any relation using powers of 2 but failed.
20 votes
2 answers
1k views

A symmetrical number sequence

What 5-letter word does this sequence represent? ...
22 votes
0 answers
2k views

REALLY important days in history

@Z. Dailey asks a mathematical puzzle Important days in history... and to come! with a series of dates in years 1973, 1978, 1983, 1992, 2005. My puzzle asks the question: What is the previous date in ...
1 vote
5 answers
2k views

What is next letter in sequence: B, D, G, J, L, ___?

My answer is P. But I am not sure as there is not sufficient data to support this. B(2), ____, G(7), ____, L(12), _____ (alternating sequence of difference 5: 2, 7, 12, 17,...) ____, D(4), ____, J(10),...
-7 votes
1 answer
187 views

Need help solving two number puzzles

1st Puzzle: Can you find the next two numbers in the sequence: 122540, 577697, ?, ? 2nd Puzzle: Solve this sequence: 28) 123456, 777, 154, ?, ? Both questions are from https://free.ultimaiq.net/nse....
5 votes
1 answer
584 views

What is the next number in the following sequence: 0, 4, 8, 21, 52, 65, 96,?

What is the next number in the following sequence: 0, 4, 8, 21, 52, 65, 96, ? To allow new users to solve this puzzle and earn reputation points, I encourage all users whose reputation is 200 or ...
5 votes
2 answers
580 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 ...
2 votes
1 answer
139 views

If 123x45 = 1, 22+222=0, 8979:4=5, 56319=2 what is 781-32=?

If 123x45 = 1, 22+222=0, 8979:4=5, 56319=2 what could be the solution to 781-32=? Found it on an maths board and became desperate over time.
6 votes
1 answer
500 views

A healthy number sequence

What should b the missing number? 1, 2, 3, 5, 6, 7, ?, 12
2 votes
3 answers
347 views

Next term in sequence [closed]

Came across these 3 sequences to find the next number denoted by '?' in a test yesterday and was unable to select the right answer from the options given 1,6,19,54,151,426,? - Options given are 1415,...
6 votes
1 answer
395 views

Find the ciphering method 2

Link to the entire series. The message: 3, 53, 48751, 9247757, 294914580539 The answer is a 13 letter word: UNDERSTANDING Hint 1:
2 votes
1 answer
964 views

What is the next term in the sequence 3, 1, -7, 41?

I could detect only one pattern, however, the sign is confusing me $3 - 1 = 1 \times 2$ $1 - (-7) = 2 \times 2^2$ $-7 - 41 = -3 \times 2^4$ I have a pattern, but I am confused due the to sign.
1 vote
0 answers
105 views

Can you find the missing letters?

A pattern of letters has had letters 10 through 20 deleted. Your job is to find out what letters should go in spots 10-20. Here is the pattern: a, b, c, d, d, d, f, e, f, _, _, _, _, _, _, _, _, _, _, ...
3 votes
1 answer
351 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, ? What is the next term in this sequence? I was asked this in an interview, but my time ran out and I couldn't figure out the pattern. I see a lot of terms of ...
5 votes
1 answer
413 views

Why do 1 and 1 complete 120, 10, 3, ?,?

This is a question from an IQ test (NSE test designed by Ivan Ivec and Theodosis Prousalis). The link for this test is https://free.ultimaiq.net/nse.htm The sequence is: 120, 10, 3, ?, ? The answer ...
15 votes
1 answer
637 views

Self-referential sequence that is sometimes powers of two

I've created an integer sequence where, after the first two elements, every element is calculated using the previous two. If the first two numbers are $1$ and $3$, the sequence goes as follows: $$1, 3,...
7 votes
1 answer
941 views

NSE puzzle: 91420512, 1297514, 35172115,?

There's another puzzle on nse that I don't know how to do. 91420512, 1297514, 35172115, ?
2 votes
2 answers
428 views

Another Number Sequence Riddle

Here is another number sequence riddle for you all: 4, 2, 7, 6, 8, __, __, and so on. What numbers go in the blanks?
3 votes
1 answer
366 views

Can you find the next number in the following series? 14, 1, 13, 0, 23, 21,?

Replace the question mark with the next number: 14, 1, 13, 0, 23, 21, ?
4 votes
1 answer
497 views

Find next element of the sequence

Source of the question: Taken from the sub-Reddit r/askmath here: https://www.reddit.com/r/askmath/comments/15ar3ne/looking_for_the_answer_to_the_following_sequence/ What is the next element of the ...
-4 votes
2 answers
419 views

4, 2, 4, 2305843009213693952, ? - an original number sequence

Here is the sequence: 4, 2, 4, 2305843009213693952, ? Source: My brain (as it was invented by me. I also attempted to search if someone else created this, but I was unable to find) Hint 1: Hint 2: (...
1 vote
1 answer
343 views

Restore a once very happy sequence

Once, I had a nice sequence of numbers.. They were all very happy. Suddenly, someone came by and stole all the lines. The numbers didn't know what to do, and got very scared. They clung to each other. ...
1 vote
0 answers
192 views

Puzzle Challenge: Unraveling the the Circular Conundrum

Known are five numbers: 1, 2, 3, 4, and 5, arranged clockwise. The number after 1 is 2, after 2 is 3, after 3 is 4, after 4 is 5, and after 5 is 1. Whenever two adjacent numbers meet, it triggers a ...
6 votes
3 answers
751 views

What's the next number? You may need some help

What's the next number in the following sequence? 1, 3, 6, 7, 9, 11, 13, 14, 18, 21, 23, 28, 31, ___, ... Hints will be released gradually - the first one is in the title. Hint #2: Additionally: ...

1
2 3 4 5
18