# Only 4 are used!

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• 05-14-2004
jlou
Of course, since you use three dimensional space. I believe the Four Color Theorem assumes a single plane. If you could create a map in two dimensions then I'd be impressed.
• 05-15-2004
Zach L.
That was my point. It is easy if you change the assumptions, and probably impossible if you don't. :)
• 05-15-2004
Perspective
alright, ill take a shot at it.

*note: black region counts as a region that needs to be coloured. I guess i could have used orange or something :rolleyes:
• 05-15-2004
anonytmouse
Change the inner black to blue and the outer black to yellow.

Quote:

http://www.math.gatech.edu/~thomas/FC/fourcolor.html
The next major contribution came from Birkhoff whose work allowed Franklin in 1922 to prove that the four color conjecture is true for maps with at most 25 regions.
So if you want to 'solve' it maybe you should try using more than 25 regions.
• 05-15-2004
scrappy
• 05-15-2004
Glirk Dient
color red gree and and the middle and outside red.
• 05-15-2004
anonytmouse
Back to kindergarten.
• 05-15-2004
ZerOrDie
Quote:

Originally Posted by axon
>>Can anyone prove me wrong?

LOL...pft, why would we prove you wrong, if you didn't come up with that.

BTW, in my data structures and discrete math class, our prof said he will give out an A for the course if anyone can prove the theroem wrong...

I bet he would seeing as it would make your prof instantly famous. No one has proved or disproved the theorem for a map of more than 25 regions. The proof published by Appel-Haken is not accepted and will not be accepted for a couple reasons.

1). Parts are done on computers and cannot be verified by hand.
2). No one has been able to check the rest of the proof in it's entirety.
• 05-15-2004
Glirk Dient
Can anyone link to a site that says in the theorem the regions cannot touch at a point? I searched and didnt find anything about that.

If no one can I will continue to think I am the winner so I feel special.
• 05-15-2004
XSquared
Quote:

The four-color theorem states that any map in a plane can be colored using four-colors in such a way that regions sharing a common boundary (other than a single point) do not share the same color.
http://mathworld.wolfram.com/Four-ColorTheorem.html
• 05-16-2004
Glirk Dient
Awwww....
• 05-16-2004
Dissata