Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site watmath.UUCP Path: utzoo!watmath!csc From: csc@watmath.UUCP (Computer Sci Club) Newsgroups: net.math Subject: Re: Interesting Numbers Message-ID: <7715@watmath.UUCP> Date: Thu, 10-May-84 21:45:48 EDT Article-I.D.: watmath.7715 Posted: Thu May 10 21:45:48 1984 Date-Received: Sat, 12-May-84 08:46:20 EDT References: <1279@uvacs.UUCP>, <1517@brl-vgr.ARPA> Organization: U of Waterloo, Ontario Lines: 23 ... Problem find sets A and B such that: (i) A union B = positive integers (ii) A intesect B = the empty set (iii) If B has a least element then this element is an element of A Solution A= positive integers, B= empty set Proof Assume B non-empty, then B has a least element, therefore by (iii) A intersect B is non-empty contradicting (ii). Therefore B is empty, therefore by (i) A= positive integers. Now call A interesting numbers and B non-interesting numbers and we have a proof that there are no non-interesting numbers. (given (i),(ii), and (iii) which as has been pointed out may not be very reasonable) I do not see any problem with the above formulation. (in particular it is not equivalent to the unexpected hanging date paradox) William Hughes