20180808, 08:10  #265  
Sep 2003
2,579 Posts 
Quote:
42 45 111318179143061 Last fiddled with by GP2 on 20180808 at 08:37 

20180808, 08:19  #266  
Einyen
Dec 2003
Denmark
3×5×193 Posts 
Quote:
Quote:
Quote:
I just tested pfgw on this factor, you just have to write the factor as 111318179143061*2^45+1 in a text file. 111318179143061*2^45+1 is a Factor of F42!!!! (0.000000 seconds) Last fiddled with by ATH on 20180808 at 08:25 

20180808, 08:35  #267  
Sep 2003
2,579 Posts 
Quote:
0<K<2^(n+2) where unlike the usual "k", this K can be even, i.e., K = 2^(m(n+2)) * k I edited my previous post to make this clear. Last fiddled with by GP2 on 20180808 at 08:37 

20180808, 13:37  #268  
Sep 2003
2579_{10} Posts 
Quote:
I ran it on a c5d.large instance on AWS (one core, Skylake, 3.0 GHz Xeon), same platform as for the GMP program. Here are the times: Code:
7905*2^352281+1 is a Factor of F352279!!!! (39.253506 seconds) vs. my GMP program = 957 sec (24 times slower) 11*2^960901+1 is a Factor of F960897!!!! (219.145612 seconds) vs. my GMP program = 7587 sec (35 times slower) vs. Gary pmfs = 47 minutes = 2820 sec (13 times slower) running on unknown system 193*2^3329782+1 is a Factor of F3329780!!!! (3428.316006 seconds) vs. my GMP program = 124205 sec (36 times slower) It's amusing that pfgw gives times to the millionth of a second... Running the precompiled staticallylinked version pfgw64s made no difference. I'm a bit alarmed for Gary though... 

20180808, 13:44  #269  
Banned
"Luigi"
Aug 2002
Team Italia
11233_{8} Posts 
Quote:
PMFS is quite impressive for N below 30,000. 

20181102, 02:30  #272 
"Gary"
Aug 2015
Texas
60_{8} Posts 
A new factor from FermatSearch
I would like to report the following new Fermat factor:
***** 19,789,270,693 * 2^2148 + 1 divides F2144 This was discovered today running pmfs on my Superdome X system. 
20181102, 10:40  #273 
Banned
"Luigi"
Aug 2002
Team Italia
11·433 Posts 

20181219, 04:01  #274 
"Gary"
Aug 2015
Texas
48_{10} Posts 
One more new factor for 2018 from FermatSearch
I am happy to report the following new Fermat factor:
***** 6,604,326,057 * 2^3347 + 1 divides F3345 This was discovered on Dec 13 running pmfs on my HPE Superdome X system. Wishing everyone a joyous holiday season and a Happy New Year! Last fiddled with by Gary on 20181219 at 04:33 
20181220, 12:13  #275 
Banned
"Luigi"
Aug 2002
Team Italia
11·433 Posts 
Two in 6 days!
December 19th, 2018
New Fermat factor from FermatSearch! 1075441212722595 . 2^{135}+1 is a Factor of F_{132}!!! Peter Strasser discovered the seventh Fermat factor of this year! He used George Woltman's mmff program running on his home computer. Congratulations to Peter from FermatSearch, for his second factor! Moderators please modify the title: Gostin factor was found on Dec. 13th.  Last fiddled with by ET_ on 20181221 at 08:43 
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