Date: Thu, 24 Aug 2006 00:56:16 -0400
From: "B. Dodson" <bad0 at Lehigh.EDU>
X-Accept-Language: en-us, en
To: Paul Zimmermann
Subject: PS on ecm paper

Dear Paul,

    Well, it's a bit late, but there's at last a p6x for ecm 2006;  a
rather nice one at 67-digits, from 10,381+ C217, with p147 cofactor.
Limits at b1=260M were again not hardly used,

[ <2, 2>, <3, 1>, <131, 1>, <124847, 1>, <1244459, 1>, <1785599, 1>,
<3000931, 1>, <4032877, 1>, <27225659, 1>, <29985143, 1>, <87373729, 1>,
<11805290281, 1> ]

so b1=87.4M would have been enough, b2=11.8e9 so 200*(2nd largest)
would have sufficed.  Still using your early 6.1 binary.
    Best Regards, Bruce
-----------
GMP-ECM 2006-03-13 [powered by GMP 4.1] [ECM]
Input number is 
1009342896093598497779073565555297793634912097024613160705050252018362252646940962166733304631155103166829723922295200013852066602135544397087747985877524133291986126801290042969097513730326998650850605170907339801 
(214 digits)
Using B1=260000000, B2=2328824422480, polynomial Dickson(30), 
sigma=834412411
Step 1 took 2516300ms
Step 2 took 932081ms
********** Factor found in step 2: 
4444349792156709907895752551798631908946180608768737946280238078881
Found probable prime factor of 67 digits: 
4444349792156709907895752551798631908946180608768737946280238078881
Probable prime cofactor 
227106988265159616528571981140572415396122551755756282296008613353922816015404819504625289055134338407924996143023758066472872886277706507970899321 
has 147 digits
Report your potential champion to Richard Brent <champs@rpbrent.com>
(see http://wwwmaths.anu.edu.au/~brent/ftp/champs.txt)