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Topic: A topological problem
Replies: 6   Last Post: Mar 2, 2013 9:39 AM

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Hauke Reddmann

Posts: 532
Registered: 12/13/04
Re: A topological problem
Posted: Feb 27, 2013 8:15 AM
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Ken Pledger <ken.pledger@vuw.ac.nz> wrote:

> Can you move a crossing past an o? If so, the thing is a planar
> graph: just move the four corner o's, top to bottom and bottom to top.


> That fulfils your condition about horizontal lines. But is there some
> other restriction on moving the crossings?


Oh. Sorry. The o are nailed to the plane and may not be moved.
(You can move the O, though.)
--
Hauke Reddmann <:-EX8 fc3a501@uni-hamburg.de
Die Weltformel: IQ+dB=const.



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