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Challenge "Number Sequence"

Challenge "Number Sequence"  

  By: admin on May 19, 2010, 10:05 a.m.

This sequence is infinite, but you may recognize it after just 13 numbers. What is the 14th number?Please type in the numeric expression of the number.
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 Last edited by: admin on Oct. 31, 2021, 2:54 a.m., edited 1 time in total.

L1 Number sequence: Choose a number you like.  

  By: senax on Oct. 16, 2010, 9:08 p.m.

As far as I know you could choose any number you like.
You always find a sequence that fits. [HTML_REMOVED]
Even tough it is not the idea in this level 1 challenge …

Re: Challenge "Number sequence"  

  By: Adam on Oct. 17, 2010, 12:48 p.m.

Is there some place in this forum where we can discuss how we arrived at the answer? I got the number right, but I'm not sure if the pattern I saw is the same pattern the original creator had in mind. I'll just leave it at that so I don't spoil anything.

Re: Challenge "Number sequence"  

  By: be on Oct. 17, 2010, 1:07 p.m.

Hello Adam,

Is there some place in this forum where we can discuss
how we arrived at the answer?

Yes, that's possible and its welcome too.

You can either use the contact formular; or send an email directly to the author of a challenge. If the author allowed us to publish his email you get it in the following way:

In the list of challenges there is on the right side of the title of each challenge an information icon.
If you click on it you see the author's email address.
(e.g. in the list on page http://www.mysterytwisterc3.com/index.p ... vel-i.html)

Re: L1 Number sequence: Choose a number you like.  

  By: HermannSW on Oct. 20, 2010, 10:16 p.m.

As far as I know you could choose any number you like.
You always find a sequence that fits. [HTML_REMOVED]
Even tough it is not the idea in this level 1 challenge …

Correct, and I found immediately two well documented different sequence continuations …
I will send an email to the author so that later he can provide that information – as you said the idea is to find "a" continuation making sense …

Re: Challenge "Number sequence"  

  By: mr66 on Oct. 20, 2010, 11:15 p.m.

the goal is to find a sequence definition so simple that its simplicity (and beauty) alone shows that it is correct. [HTML_REMOVED]
if your are not sure - then it's probably not simple enough

Re: Challenge "Number sequence"  

  By: joschi on Oct. 21, 2010, 10:20 p.m.

for every real number i can find a polynomial, that has the given numbers plus this chosen number as roots. To fulfill your call for beauty, i choose this number natural and bigger than the others - 256 or 1337?

Challenge "Number Sequence - Part 1  

  By: Jarhead1801 on April 13, 2012, 5:30 a.m.

I have always enjoyed riddles. This is my first time on this site and as a blue collar guy with only a high school education. I find my notes for solving this "riddle" interesting. What do you all think and how can I improve my solving speed?

here are my notes:

Q: 1 - 2 - 4 - 6 - 10 - 12 - 16 - 18 - 22 - 28 - 30 - 36 - 40 - ?
A: xxx
1+1=2 2+2=4 4+4≠6
n + (n x .5)= nope
1 2 2 4 2 4 2 4 6 4 6 4 48? (incorrect 14 tries left)
Is this the point that the pattern repeats itself 41? (incorrect 13 tries left)
Do not google it…. I never did have much self control but I know -213 isnt the answer.
f(n) = n*n + 1 (now how do I decipher this math equation)
1 1 0 2 -2 2 -2 2 2 -2 2 -2 xxx? (CORRECT \o/)

Re: Challenge "Number Sequence - Part 1  

  By: be on April 13, 2012, 4:37 p.m.

Here are my notes:
Q: 1 - 2 - 4 - 6 - 10 - 12 - 16 - 18 - 22 - 28 - 30 - 36 - 40 - ?

It's ok to discuss approaches how to solve a challenge but don't tell the solution (so I changed it to xxx). You assumed a number to be the solution: Was this a guess or did you google it? If you need to discuss telling the solution please send a private email from the forum to the MTC3 team or the author of a challenge.

So far there is no formula known to this sequence. Its based on a very special kind of numbers. If you get the idea, it's easy.
The sequence is infinite and without cycles. The next few elements after the ? are: - 46 - 52 - 58 - 60 -
Maybe you noticed that all numbers beside the first one are even.

Re: Challenge "Number Sequence"  

  By: freak115 on April 24, 2013, 1:14 a.m.

[HTML_REMOVED] the solution is ultra lame….
i expected a different pattern.. but perhaps keys or patterns are always a think of good taste…

Re: Challenge "Number Sequence — Part 1  

  By: tux77 on Feb. 9, 2015, 8:40 p.m.

Hi,

=========================

"SOLVED" "SOLVED" "SOLVED"

Thank for answer and sorry for my bad english.

Great from Paris,

Tux

 Last edited by: tux77 on March 3, 2015, 5:06 p.m., edited 2 times in total.

Re: Challenge  

  By: tux77 on Feb. 9, 2015, 8:45 p.m.

Hi,

Im very begginer in maths and more on cryptanalyse probleme i had no degree im not bachelor but i like using my mind and i want to try solve easy problem.

'Sequence number 1' is hard for me but i think a i have an idea but i have a problem im my thinking.
I think its the sequence number of the first primal number -1 but i'm not sure.
Why there is the "2" number who is primal no? or its the reduction of (primal number 3)-1? and the one is the 'primal number 2)-1?
Its a good reasoning ?

Thank for answer and sorry for my bad english.

Great from Paris,

Tux

Re: Challenge "Number Sequence — Part 1  

  By: be on Feb. 23, 2015, 9:59 a.m.

Its a good reasoning ?
Thank for answer and sorry for my bad english.
Great from Paris,

Hello tux77,
Your reasoning is correct.
Maybe, you already revealed too much of the solution :-) However, it's a thin line between meaningful discussions in the forum and uncovering a bit too much.
Don't worry about your English, we could understand it. Maybe, you could use a spell checker in the future before sending.
If you already solved this challenge in the meantime you may add this information to your forum post.
Kind regards back to Paris.


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