Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site umcp-cs.UUCP Path: utzoo!watmath!clyde!cbosgd!gatech!seismo!umcp-cs!dsn From: dsn@umcp-cs.UUCP (Dana S. Nau) Newsgroups: net.ai Subject: Re: Re: A halting problem Message-ID: <2752@umcp-cs.UUCP> Date: Tue, 14-Jan-86 20:26:11 EST Article-I.D.: umcp-cs.2752 Posted: Tue Jan 14 20:26:11 1986 Date-Received: Fri, 17-Jan-86 02:46:51 EST References: <2175@aecom.UUCP> <2540002@csd2.UUCP> <2191@aecom.UUCP> Reply-To: dsn@maryland.UUCP (Dana S. Nau) Organization: U of Maryland, Computer Science Dept., College Park, MD Lines: 23 In article <2191@aecom.UUCP> berger@aecom.UUCP (Micha Berger) writes: >> [] >> > The human mind, on the other hand, given enough time an >> > practice, can find an endless loop in any procedure. >> >> Does the following procedure contain an endless loop? >> >> for (each possible quadruple of natural numbers, >> in any systematic order) >> if (a**n + b**n == c**n) >> halt(); >> > >Given 10^19 years, I think I could do it. (We said theoretically possible, >not realistic (-: How do you propose to do this? If it doesn't halt after 10^19 years, are you going to claim that it won't ever halt? How do you know it won't halt after 10^19 + 1 years? -- Dana S. Nau, Comp Sci Dept, U of Maryland, College Park, MD 20742 dsn@maryland seismo!umcp-cs!dsn (301) 454-7932