Path: ...!news.misty.com!weretis.net!feeder9.news.weretis.net!i2pn.org!i2pn2.org!.POSTED!not-for-mail From: joes Newsgroups: sci.math Subject: Re: How many different unit fractions are lessorequal than all unit fractions? (infinitary) Date: Mon, 7 Oct 2024 15:18:30 -0000 (UTC) Organization: i2pn2 (i2pn.org) Message-ID: References: <8ce3fac3a0c92d85c72fec966d424548baebe5af@i2pn2.org> <55cbb075e2f793e3c52f55af73c82c61d2ce8d44@i2pn2.org> <4bc3b086-247a-4547-89cc-1d47f502659d@tha.de> <0f95c2ba186e7c007b2e947aad0e3f4d6177e196@i2pn2.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Injection-Date: Mon, 7 Oct 2024 15:18:30 -0000 (UTC) Injection-Info: i2pn2.org; logging-data="952087"; mail-complaints-to="usenet@i2pn2.org"; posting-account="nS1KMHaUuWOnF/ukOJzx6Ssd8y16q9UPs1GZ+I3D0CM"; User-Agent: Pan/0.145 (Duplicitous mercenary valetism; d7e168a git.gnome.org/pan2) X-Spam-Checker-Version: SpamAssassin 4.0.0 Bytes: 2894 Lines: 29 Am Mon, 07 Oct 2024 11:08:33 +0200 schrieb WM: > On 07.10.2024 10:05, joes wrote: >> Am Mon, 07 Oct 2024 09:41:23 +0200 schrieb WM: >>> On 06.10.2024 17:48, Alan Mackenzie wrote: >>> even an unbounded sequence does not get longer when shifted by one >>> step. >> Nor does it get shorter, it stays infinite. > It keeps all its elements but not more. „More” being a different kind of infinity, namely at least uncountable. All ω+k are equally infinite. >> Bijection is not about completeness, countability is. > Bijective means injective and surjective. Exactly, which is the case for every finite subset. >> Of course stopping after a finite number, which potential infinity >> seems to mean, is not „complete” in that sense. Hilbert’s Hotel is >> actually infinite, it already holds infinite guests. > Name them by all the natural numbers. Then no further guest can appear. It can, if I begin numbering with 2. The cardinality of N\{1} can’t be finite. >> All of them can at once move to the next room, > All rooms are enumerated by all the natural numbers. Hence there is no > chance to move. Only in potential infinity there is. Huh? They are all fixed, we can move them „rigidly”. -- Am Sat, 20 Jul 2024 12:35:31 +0000 schrieb WM in sci.math: It is not guaranteed that n+1 exists for every n.