🚀 go-pugleaf

RetroBBS NetNews Server

Inspired by RockSolid Light RIP Retro Guy

Article View: sci.crypt
Article #500

Re: New record non-networked factorization of difficult number

#500
From: Dan Bernstein
Date: Sat, 25 Jul 1992 14:53
27 lines
1499 bytes
In a reply to Bob Silverman I wrote:
> (2^488 + 1)/257 had 146 digits, last I counted.

Which proves once and for all that number theorists can't count. :-)
The factorization is still the record non-networked factorization, of
course, but (2^488 + 1)/257 has only 145 digits. While I'm at it let me
correct my assertion that 2^512 + 1 is the record difficult number; the
record difficult number is (2^512 + 1)/2424833, which has 148 digits.

In case anyone's wondering, I was misled by the UNIX dc program, which
acts like this:

% dc
2 488^ 1+ 257/p
310960166879725296199878945847101390767175534833553546544725362515212\
1265127859917318281565697486165824574686253229943428928722855633467075\
526401
10 145^p
1000000000000000000000000000000000000000000000000000000000000000000000\
0000000000000000000000000000000000000000000000000000000000000000000000\
000000

Notice how the first line of output is chopped off a digit early. This
is what I get for counting digits with the help of a computer instead of
by hand.

---Dan
Technical Details
Message-ID: <28087.Jul2514.53.0492@virtualnews.nyu.edu>
Path: arc1-ca.pugleaf.net!sparky!uunet!sun-barr!ames!agate!ucbvax!virtualnews.nyu.edu!brnstnd
References: <BrwFFH.CAt@cs.psu.edu> <1992Jul25.004256.4641@linus.mitre.org> <25367.Jul2504.27.2692@virtualnews.nyu.edu>

Show Full Headers
Complete Article Headers
Path: arc1-ca.pugleaf.net!sparky!uunet!sun-barr!ames!agate!ucbvax!virtualnews.nyu.edu!brnstnd
From: brnstnd@nyu.edu (Dan Bernstein)
Newsgroups: sci.crypt
Subject: Re: New record non-networked factorization of difficult number
Message-ID: <28087.Jul2514.53.0492@virtualnews.nyu.edu>
Date: 25 Jul 92 14:53:04 GMT
References: <BrwFFH.CAt@cs.psu.edu> <1992Jul25.004256.4641@linus.mitre.org> <25367.Jul2504.27.2692@virtualnews.nyu.edu>
Organization: IR
Lines: 27