I'm pretty sure we were taught it the other way. In fact, both of these definitions are quite common. (Unfortunately.) I personally prefer the >= 0 definition, for two reasons: 1) It corresponds (subject to overflow) to types used in programming languages. 2) "Positive integer" is a reasonable alternative expression for the > 0 definition, whereas the best available for the >= 0 definition - "non-negative integer" - is more awkward and, as it contains a negation, more easily confused. Franklin T. Adams-Watters 16 W. Michigan Ave. Palatine, IL 60067 847-776-7645 -----Original Message----- From: Cordwell, William R <wrcordw@sandia.gov> To: math-fun <math-fun@mailman.xmission.com> Sent: Mon, 10 Apr 2006 13:23:42 -0600 Subject: RE: [math-fun] high school mathematics I have seen various college texts that define natural numbers to be the integers

0, and others the integers >= 0. I'm fairly certain, that, in middle school, we were taught that the natural numbers were positive.

BC -----Original Message----- From: math-fun-bounces+cordwell=sandia.gov@mailman.xmission.com [mailto:math-fun-bounces+cordwell=sandia.gov@mailman.xmission.com]On Behalf Of Henry Baker Sent: Monday, April 10, 2006 12:47 PM To: James Propp Cc: math-fun@mailman.xmission.com Subject: Re: [math-fun] high school mathematics Unfortunately, I haven't found mathematicians in college to necessarily be any more punctilious than those in high school when it comes to universal agreement on terminology. _______________________________________________ math-fun mailing list math-fun@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/math-fun ___________________________________________________ Try the New Netscape Mail Today! Virtually Spam-Free | More Storage | Import Your Contact List http://mail.netscape.com