翻訳と辞書 |
Lehmer's totient problem : ウィキペディア英語版 | Lehmer's totient problem
In mathematics, Lehmer's totient problem, named for D. H. Lehmer, asks whether there is any composite number ''n'' such that Euler's totient function φ(''n'') divides ''n'' − 1. This is true of every prime number, and Lehmer conjectured in 1932 that there are no composite solutions: he showed that if any such ''n'' exists, it must be odd, square-free, and divisible by at least seven primes (i.e. ω(''n'') ≥ 7). Such a number must also be a Carmichael number. ==Properties==
* In 1980 Cohen and Hagis proved that ''n'' > 1020 and that ω(''n'') ≥ 14.〔Sándor et al (2006) p.23〕 * In 1988 Hagis showed that if 3 divides ''n'' then ''n'' > 101937042 and ω(''n'') ≥ 298848.〔Guy (2004) p.142〕 * The number of solutions to the problem less than ''X'' is .〔Sándor et al (2006) p.24〕
抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Lehmer's totient problem」の詳細全文を読む
スポンサード リンク
翻訳と辞書 : 翻訳のためのインターネットリソース |
Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.
|
|