[QUOTE=Stargate38;287363]Do you have an ETA? This number is #5 among the 10 smallest composites in the Repunit Factorizations:

[URL]http://homepage2.nifty.com/m_kamada/math/11111.htm[/URL]

I love to see the new factors. It makes me happy. :smile:[/QUOTE][QUOTE=schickel;282649]I'd be willing to pay $5 if you factored it and then posted the factors a digit at a time over the course of a week...:missingteeth:[/QUOTE]This offer is still open....:grin:

Sun Jan 29 00:17:21 2012 prp75 factor: 139397282236319122569927698220829009751930337603755594300386510230285560351
Sun Jan 29 00:17:21 2012 prp92 factor: 32647385051525041661479792654516355809315046496410663779745524799749707387460867800164362111

Chris K

PS. M. Kamada hasn't heard of anyone else working on R870 so I'll start on it. I think ECM to 50 digits is enough, T55 would take about two weeks for a 10% chance of a factor while GNFS will take 4-5 weeks for a 100% chance.

I think you should chat with Yousuke Koide first before you start the fatoring of M870, he has done 18400@12e7 of M870, and this number is marked with (reserved GNFS) ,
the url is
[url]http://www.h4.dion.ne.jp/~rep/table3.htm[/url]
you can have his email from [url]http://www.h4.dion.ne.jp/~rep/[/url]

Bo Chen

FWIW, my computer ran 673 curves at B1=11e6 before I saw your message and ended the tasks.
No factor found, unsurprisingly, if the number has already received more than t55 ECM work :smile:

[QUOTE=Batalov;287445]Also, if you do want to take on a c166 [strike]c162[/strike], then why not on a Wanted Cunningham c163? It was deliberately left for enthusiasts.[/QUOTE]
This is a much safer offer. This number ([URL="http://homes.cerias.purdue.edu/%7Essw/cun/want122"]3^710+1 cofactor[/URL]) is still unreserved - write to Sam.

OK, I'll leave it to Yousuke Koide. He reserved it first.

Chris