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From: segre@uicsl.UUCP
Newsgroups: net.ai
Subject: Re: Fermat's Last Theorem - (nf)
Message-ID: <5540@uiucdcs.UUCP>
Date: Sat, 11-Feb-84 22:42:56 EST
Article-I.D.: uiucdcs.5540
Posted: Sat Feb 11 22:42:56 1984
Date-Received: Tue, 14-Feb-84 01:16:19 EST
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#R:sri-arpa:-1640300:uicsl:15500024:000:662
uicsl!segre    Feb 10 10:12:00 1984

The four color conjecture of (Guthrie 1852), "Every planar graph is 
four-colourable," was proved correct by Appel and Haken at the
University of Illinois. This is the "ugly" computer proof you refer to.
[Bull. Amer. Math. Soc., 82]. This proof is considered correct - claims
to "ugliness" are due to the method used which required large amounts
of computer time to prove four-colourability of an exhaustive set of
subgraphs. There is nothing "ugly" about the method, except that before
the availability of computers it wouldn't have been possible to use such a
method.

As of today there is no other proof that I know of.


Alberto Segre
...uiucdcs!uicsl!segre