Path: ...!eternal-september.org!feeder2.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: Moebius Newsgroups: sci.math Subject: Re: How many different unit fractions are lessorequal than all unit fractions? (infinitary) Date: Sat, 2 Nov 2024 14:03:16 +0100 Organization: A noiseless patient Spider Lines: 33 Message-ID: References: <88e6a631-417a-4dd0-9443-a57116dcbd28@att.net> <7a1e34df-ffee-4d30-ae8c-2af5bcb1d932@att.net> <6a90a2e2-a4fa-4a8d-83e9-2e451fa8dd51@att.net> <0e5fb47d-60f7-42bb-beec-4a9661c807da@tha.de> <244b3e8e460c67e32d8b4d57670e4f881c1ac716@i2pn2.org> <9b4cc8f7e6cfb37f890fa1add31b4378e6c727cb@i2pn2.org> Reply-To: invalid@example.invalid MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Sat, 02 Nov 2024 14:03:17 +0100 (CET) Injection-Info: dont-email.me; posting-host="9307dcd9bec6ccad65fdbb2ad1fbdbff"; logging-data="3997517"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1+WC/vr2ZpJXBnAjyTHjB4W" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:LVZgsGas9eVQf/drNS6KcG4QFY8= In-Reply-To: <9b4cc8f7e6cfb37f890fa1add31b4378e6c727cb@i2pn2.org> Content-Language: de-DE Bytes: 2983 Am 02.11.2024 um 13:30 schrieb joes: > Am Fri, 01 Nov 2024 11:07:27 +0100 schrieb WM: >> On 31.10.2024 21:46, joes wrote: >> >>> At single points a function has a single value, not a jump. >> It jumps in case of NUF by 1 at a unit fraction with respect to the >> foregoing unit fraction and the many points between both. > Whether you define your pathological function with < or <=, at every > point it has one value (note it doesn't have the SAME value at every > point [...]). > >>> In the case of NUF, [we have:] NUF(x) = 0 for x = 0 and NUF(x) = aleph_0 for all x e IR, x > 0. Instead of NUF we might consider the function NNN(x) = card {n e IN: n > x} (x e IR*) "number of natural numbers larger than x" defined on the extended reals (R* = IR u {-oo, oo}). THERE we would have: NNN(x) = 0 for x = oo. NNN(x) = aleph_0 for all x e IR*, x < oo. Math is too hard for Mückenheim.