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No First-Hand-Neighbors!!



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10 replies to this topic

#1 BMAD

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Posted 06 July 2013 - 09:20 PM

Create the shortest possible sequence (using numbers from 1,2,...n) such that no number is next to its first-hand neighbors (e.g. the number 2 cannot be next to numbers 1 and 3, which are its first-hand neighbors).

 

e.g.

 

1,6,3,5,2,4,7  Here is a sequence using 7 numbers that meets the requirement.


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#2 Nins_Leprechaun

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Posted 06 July 2013 - 10:41 PM   Best Answer

Spoiler for

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#3 bonanova

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Posted 07 July 2013 - 06:29 AM

Spoiler for how about

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#4 witzar

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Posted 07 July 2013 - 03:37 PM

Clearly empty sequence (length 0) wins the contest..
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#5 BMAD

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Posted 07 July 2013 - 04:52 PM

the sequence must start at 1 and go to some n (consecutively) where n does not equal 1.


Edited by BMAD, 07 July 2013 - 04:53 PM.

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#6 witzar

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Posted 07 July 2013 - 05:00 PM

the sequence must start at 1 and go to some n (consecutively) where n does not equal 1.

Now it's a different story. BTW "best answer" sequence starts with 3 not with 1.


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#7 BMAD

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Posted 07 July 2013 - 05:40 PM

I am sorry, I am working on translating to English better. I mean to say that the numbers you use must contain the sequence from 1 to some N but don't have to start that way. So 1, 3, 5, 2, and 4 are fine since it contains numbers 1-5 and no first hand neighbors.
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#8 bonanova

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Posted 08 July 2013 - 01:59 AM

It was clear to me what you were asking.
I just included, for fun, something outside the "box".

Your English is fantastically good, even for a first-language writer,
No need to apologize. ;)

Did I hear somewhere that Russian is your first language?
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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

#9 BMAD

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Posted 08 July 2013 - 03:29 AM

My first language is Ukrainian but I do speak Russian sufficiently.


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#10 bonanova

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Posted 10 July 2013 - 10:55 AM

My first language is English and I'm still learning it. My writing is OK but my speech needs work. :blush:


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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell




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