Path: ...!weretis.net!feeder8.news.weretis.net!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: "Chris M. Thomasson" Newsgroups: sci.math Subject: Re: How many different unit fractions are lessorequal than all unit fractions? (infinitary) Date: Mon, 14 Oct 2024 15:27:14 -0700 Organization: A noiseless patient Spider Lines: 38 Message-ID: References: <4bc3b086-247a-4547-89cc-1d47f502659d@tha.de> <3f5fcf13171337f1c3d2ef84cc149be327648451@i2pn2.org> <97b84c07aa526903a0788584f7f7ae9121f8b81f@i2pn2.org> <60f1280e-e226-4314-8eca-da5410be8ca3@tha.de> <96a7aa944085e76faed69c8db9a8dca599e1a159@i2pn2.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Tue, 15 Oct 2024 00:27:15 +0200 (CEST) Injection-Info: dont-email.me; posting-host="622b3858c7e397e9bc334577319143ad"; logging-data="1445698"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1+JZWoSJD3yqTdWTjPTMhaQmTs2On7J4Zo=" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:FiJc4+oYflE7QI2EjKhBRUPjA+o= Content-Language: en-US In-Reply-To: Bytes: 2926 On 10/14/2024 9:37 AM, WM wrote: > On 14.10.2024 18:04, joes wrote: >> Am Mon, 14 Oct 2024 15:40:01 +0200 schrieb WM: >>> On 14.10.2024 14:15, joes wrote: >>> >>>> No, we are taking the complete, actually infinite set which reaches to >>>> "before" w. >>> and fills the space between 0 and ω evenly. Same happens with the >>> doubled set between 0 and ω2. >> No, there is no consequent infinity. The even numbers do not go >> 0, 2, 4, ..., w, w+2, w+4, ..., w*2 > > Either the doubled numbers are natural, then half of them have not been > among the original set, or all natural numbers have been doubled, then > the result contains infinite numbers. > > That doubling _all_ natural numbers only yields _all_ natural numbers is > impossible. Take the index, using natural numbers 1: { 1 } 2: { 1, 2 } 3: { 1, 2, 3 } 4: { 1, 2, 3, 4 } .... vs: 1: { 2 } 2: { 2, 4 } 3: { 2, 4, 6 } 4: { 2, 4, 6, 8 } ....