Wednesday 28 November 2007

C127_113_36

Well, I finally completed my factorization of C127_113_36 for the XYYXF project - and by the recommended method - ie sieving by GGNFS, followed by post-processing with msieve. Thanks to Greg Childers, Bob Backstrom and Hallstein Hansen, who helped me with this transfer.
Basically msieve needs three files:
1) worktodo.ini - just containing the input number
2) msieve.fb - with the details (roughly) transferred from the .poly file of GGNFS
3) msieve.dat - with all the actual relations from GGNFS, translated to msieve format by procrels w/ the following crucial command:
"procrels -fb C127_113_36.fb -prel rels.bin -dump"

After this it's just a case of running msieve w/
"msieve -nc -v"
In the end the sieving [Lintel] took me about 3 months(!), because of memory limitations, and the GGNFS 'bounce', while the postprocessing in msieve [PPC-Tiger] finished to schedule in less than 2 days.

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