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Topic: 4 colors problem
Replies: 86   Last Post: Mar 13, 2014 4:36 PM

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 stumblin' in Posts: 58 Registered: 3/3/14
Re: 4 colors problem
Posted: Mar 5, 2014 7:04 PM
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Oh I think I found the solution.
This time everything leads to right answer.
There is a unit pattern more fundamental than the original one.
Instead of,
a b c d
c d a b

Use,
a b
c d

Follow the same rule for coloring more countries
a b a b a b
c d c d c d

b a b
c d c d

c d
a b <-- unit pattern
c d <-- unit pattern
a b
c d

This works flawlessly even with a country whose horizontal length is bigger than others on the map.
In the process of disproving a theorem I became a complete believer.
The theorem was proposed during the time when there was no computer.
The (modified and simplified) theorem is proved without using a computer.

Date Subject Author
3/3/14 stumblin' in
3/3/14 Brian Q. Hutchings
3/3/14 stumblin' in
3/4/14 g.resta@iit.cnr.it
3/3/14 stumblin' in
3/4/14 stumblin' in
3/4/14 g.resta@iit.cnr.it
3/4/14 stumblin' in
3/4/14 stumblin' in
3/4/14 stumblin' in
3/4/14 stumblin' in
3/4/14 stumblin' in
3/4/14 g.resta@iit.cnr.it
3/4/14 magidin@math.berkeley.edu
3/4/14 stumblin' in
3/4/14 Port563
3/4/14 stumblin' in
3/4/14 Brian Q. Hutchings
3/4/14 stumblin' in
3/4/14 stumblin' in
3/4/14 stumblin' in
3/4/14 stumblin' in
3/4/14 Port563
3/4/14 stumblin' in
3/4/14 Brian Q. Hutchings
3/4/14 stumblin' in
3/4/14 stumblin' in
3/4/14 Brian Q. Hutchings
3/4/14 g.resta@iit.cnr.it
3/4/14 stumblin' in
3/4/14 Port563
3/4/14 stumblin' in
3/5/14 stumblin' in
3/5/14 magidin@math.berkeley.edu
3/5/14 stumblin' in
3/5/14 magidin@math.berkeley.edu
3/5/14 quasi
3/5/14 stumblin' in
3/5/14 magidin@math.berkeley.edu
3/5/14 stumblin' in
3/5/14 quasi
3/5/14 magidin@math.berkeley.edu
3/5/14 Brian Q. Hutchings
3/5/14 stumblin' in
3/5/14 magidin@math.berkeley.edu
3/5/14 stumblin' in
3/5/14 Brian Q. Hutchings
3/5/14 Virgil
3/5/14 stumblin' in
3/5/14 stumblin' in
3/5/14 stumblin' in
3/5/14 stumblin' in
3/5/14 stumblin' in
3/5/14 stumblin' in
3/5/14 Virgil
3/5/14 stumblin' in
3/6/14 Virgil
3/6/14 Virgil
3/6/14 Brian Q. Hutchings
3/6/14 stumblin' in
3/6/14 ross.finlayson@gmail.com
3/7/14 Brian Q. Hutchings
3/7/14 Robin Chapman
3/6/14 stumblin' in
3/6/14 stumblin' in
3/7/14 magidin@math.berkeley.edu
3/7/14 Peter Percival
3/7/14 Peter Percival
3/6/14 stumblin' in
3/7/14 stumblin' in
3/7/14 magidin@math.berkeley.edu
3/7/14 Peter Percival
3/7/14 Peter Percival
3/7/14 stumblin' in
3/7/14 stumblin' in
3/9/14 stumblin' in
3/9/14 Peter Percival
3/9/14 stumblin' in
3/9/14 magidin@math.berkeley.edu
3/9/14 Brian Q. Hutchings
3/9/14 stumblin' in
3/9/14 stumblin' in
3/11/14 stumblin' in
3/11/14 Brian Q. Hutchings
3/13/14 stumblin' in
3/13/14 Brian Q. Hutchings
3/13/14 stumblin' in

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