Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!linus!decvax!mcnc!unc!ulysses!mhuxl!ihnp4!inuxc!pur-ee!uiucdcs!uicsl!segre 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 Lines: 18 #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