From iad@MATH.BAS.BG Mon Jul 10 00:10:17 2000 Return-Path: Received: (qmail 6140 invoked from network); 10 Jul 2000 07:10:17 -0000 Received: from unknown (10.1.10.27) by m2.onelist.org with QMQP; 10 Jul 2000 07:10:17 -0000 Received: from unknown (HELO argo.bas.bg) (195.96.224.7) by mta1 with SMTP; 10 Jul 2000 07:10:16 -0000 Received: from banmatpc.math.bas.bg (root@banmatpc.math.bas.bg [195.96.243.2]) by argo.bas.bg (8.11.0.Beta1/8.9.3/Debian 8.9.3-6) with ESMTP id e6A7A9S27435 for ; Mon, 10 Jul 2000 10:10:13 +0300 Received: from iad.math.bas.bg (iad.math.bas.bg [195.96.243.88]) by banmatpc.math.bas.bg (8.9.3/8.9.3) with SMTP id KAA21664 for ; Mon, 10 Jul 2000 10:10:08 +0300 X-Mozilla-Status2: 00000000 Message-ID: <3968483B.CBFB7C7E@math.bas.bg> Date: Sun, 09 Jul 2000 12:39:07 +0300 X-Mozilla-Draft-Info: internal/draft; vcard=0; receipt=0; uuencode=0; html=0; linewidth=0 X-Mailer: Mozilla 4.6 [en] (Win98; I) X-Accept-Language: en MIME-Version: 1.0 To: lojban@egroups.com Subject: Re: [lojban] 2 maths questions References: <20000707235414.61690.qmail@hotmail.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit From: Ivan A Derzhanski X-Yahoo-Message-Num: 3528 Jorge Llambias wrote: > It is of course possible to define some new mathematical function > that assigns to the integers twice the value that it assigns > the even numbers (the function proposed taking limits is > probably the best), Here is another: What is the probability that any randomly chosen integer number is even? Answer: 1/2. To compare the thicknesses of any two sets, divide the two probabilities. So {n | n is not divisible by 3} is twice as thick as {n | n is}, because a random number is twice more likely not to be divisible by 3 than to be. Slightly more concise than the version with the limits. > but what do we want it for? Don't we all love mathematical fallacies? Rob Speer wrote: > I'm surprised there isn't already a lujvo for "prime number". How about: > > ralnamcu (ralju+namcu) x1 is a prime number of mathematical field x2 > by convention x3 I think I would interpret that as `base of number system' or something. There are many ways in which a number can be principal/chief. Incidentally, in Russian prime numbers are called (lit.) `simple numbers'. Makes sense, since the antonym is `composite numbers'. (So that's `simple' as in `composed of a single part or unit', not as `not difficult or complicated'.) michael helsem wrote: > puzuku mi pilno lu narselfendi li'u This one seems optimal. I take it divisibility by one and oneself can be conventionally ignored? --Ivan