Unanswered Questions
18 questions with no upvoted or accepted answers
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 ...
6
votes
0
answers
253
views
Sequence puzzle: 3, 9, 27
A twist of the classic sequence game:
A friend asked me to find the rule to this sequence: 3, 9, 27.
I am allowed to suggest other sequences to test if they follow that (unknown to me) rule, to which ...
6
votes
0
answers
301
views
Find the missing element?
I've been trying to solve this for quite some time, can you help me solve it?
This puzzle was made by one of my friend's teachers. This is not copyrighted and cannot be found anywhere on the internet.
...
5
votes
0
answers
263
views
Longest Fibonacci word
Fibonacci words are defined as $F_0 = a, F_1 = b, F_{n+2} = F_nF_{n+1}$ where $a, b$ are letters. How can you find the longest Fibonacci sub-word in a given string?
Try to solve it in linear time ($O(...
4
votes
0
answers
331
views
Lucas's interesting cipher
Lucas was fooling around with some letters when he encoded some text into Gsobj lwmtkd sbceugb vfy rgdjb.. Can you figure out the original text he had?
4
votes
0
answers
233
views
The smallest number
Some time ago I created a program to generate a table, and printed the first seven rows and columns.
Somehow however I forgot to print the headers and the title of the table.
I only remember that it ...
4
votes
1
answer
560
views
Formula for the sequence 1, 1, 1, 21, 3, 1, 4, 1, 5, 1, 6, ... if the 21 isn't a mistake
The sequence 1, 1, 1, 21, 3, 1, 4, 1, 5, 1, 6, ... appeared in one of my tutorial sheets in 2019. I assumed that the fourth term, 21, was a mistake (was supposed to be ..., 2, 1, ...) then it made ...
4
votes
1
answer
572
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 ...
3
votes
0
answers
120
views
Finding the next number in this sequence: 184275, 8292375, 3108105, ...,
I created this puzzle myself. Find the next number in this sequence and explain:
184275,
8292375,
3108105,
54729675,
147349125,
1587160575,
24135786675,
20906353125,
214266677625,
1676096296875,
...
3
votes
0
answers
155
views
The Mono-Quantum Condrum
You are presented with a locked box, and on its surface, you notice a sequence of peculiar symbols:
⌬ ⌅ ⊙ ⊡
Next to the symbols, there's an inscription:
...
3
votes
0
answers
171
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, ...
2
votes
0
answers
154
views
Sequence of shapes with lines and dot
This is another puzzle from Lanrt-F IQ test that was posted on Reddit
https://www.reddit.com/media?url=https%3A%2F%2Fpreview.redd.it%2Fmy-favourite-2-problems-from-lanrt-f-v0-58puclks5a6d1.png%3Fwidth%...
2
votes
0
answers
315
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, ...
1
vote
0
answers
113
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, _, _, _, _, _, _, _, _, _, _, ...
1
vote
0
answers
144
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 ...