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Article #2794Re: Oh yeah? Factor this...
From: Robert D. Silverman
Date: Fri, 22 Jan 1993 01:36
Date: Fri, 22 Jan 1993 01:36
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In article <1993Jan22.004018.2036@csi.uottawa.ca> cbbrowne@csi.uottawa.ca (Christopher Browne) writes: stuff deleted.... :ciphering scheme. There may be some better methods of searching for :factor candidates, but there aren't any "silver bullets," or algorithms :that can factor numbers in time on O(log N) time. Factoring seems to take :O(sqrt N) time, which just don't cut it. Not quite. The best rigorously proved upper bound is exp((1+o(1) sqrt(log N log log N)) The Number Field Sieve [on some reasonable unproved assumptions] takes exp( (c + o(1)) (log N)^1/3 (log log N)^2/3) with c ~ 1.91 These are both sub-exponential and considerably better than O(sqrt(N)). Even the older Pollard Rho, Squfof and FFT-based P-1 achieved O(N^1/4), not O(sqrt(N)). -- Bob Silverman These are my opinions and not MITRE's. Mitre Corporation, Bedford, MA 01730 "You can lead a horse's ass to knowledge, but you can't make him think"
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Newsgroups: sci.crypt,sci.math Path: arc1-ca.pugleaf.net!sparky!uunet!gatech!usenet.ins.cwru.edu!agate!linus!linus.mitre.org!gauss!bs From: bs@gauss.mitre.org (Robert D. Silverman) Subject: Re: Oh yeah? Factor this... Message-ID: <1993Jan22.013643.10520@linus.mitre.org> Sender: news@linus.mitre.org (News Service) Nntp-Posting-Host: gauss.mitre.org Organization: Research Computer Facility, MITRE Corporation, Bedford, MA References: <1993Jan21.011510.24294@linus.mitre.org> <1993Jan21.205045.13877@netcom.com> <1993Jan22.004018.2036@csi.uottawa.ca> Distribution: na Date: Fri, 22 Jan 1993 01:36:43 GMT Lines: 28