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Need help with this puzzle

  1. Dec 1, 2004 #1
    Hi everyone. I've been stumped trying to figure this one out for the past week, I think some may have seen it before. It looks like this:

    *EDIT* The picture I attempted to draw didn't post right, I'll have one up soon.

    *EDIT 2* Here we go:
    http://members.lycos.co.uk/evilx22/hpbimg/Untitled-1 copy.jpg

    What you have to do is draw one continuous line through every line segment on the puzzle, without going through one twice and the line can never cross itself. I'm hoping some have seen this before, so any help would be appreciated.
     
    Last edited: Dec 1, 2004
  2. jcsd
  3. Dec 1, 2004 #2
    Its impossible... you can prove it with graph theory.

    This was posted previously and there was a link to a site that had a general proof that it cant be done under certain conditions and this puzzle fit the conditions...
     
  4. Dec 1, 2004 #3

    NoTime

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    You could draw this on a Mobius strip.
    That would fix the problem.
     
  5. Dec 1, 2004 #4

    Gokul43201

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    There's an infuriatingly long thread dedicated to this problem here

    The short answer is that it is impossible to do this, if the picture is drawn on a plane, unless you cheat by going through a corner or using a giant marker, or some such thing. The proof is found in post #5 (by NateTG) in the above linked thread.
     
  6. Dec 2, 2004 #5

    NoTime

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    Isn't the Mobius surface considered to be a plane?
    A toroid or sphere, two solutions in the thread you refered to, would not be.
     
  7. Dec 2, 2004 #6

    Gokul43201

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    No, a mobius strip is not homeomorhic to a (projective) plane.

    (Additional Info : the mobius strip has an Euler Characteristic = 0, while this is 1 for a plane)
     
  8. Dec 2, 2004 #7

    NoTime

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    Interesting.
    So it would be related to a cylinder somehow?
    Does this remain true if the dimensionality changes?
    I vaguely recall something special about this as well as klein bottle for N other than 3.
     
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