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Old 2012-12-18, 07:29   #7
xilman's Avatar
May 2003
Down not across

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Originally Posted by Sam Kennedy View Post
What needs to be done differently? At the minute I'm simply adding the factor to the factor base, and I've already seen a significant speed increase, but if I could avoid doing that it would also help.

I thought because both partial relations will have a 1 in the same column, you can add them both to the relations list/matrix without any problems, however the code didn't work until I added the number to the factor base.

The traditional way is to store all the relations until you have "enough", then run a post-processing pass which repeatedly finds the large primes which occur only once in the entire set and discards the corresponding relations. After this is complete, all large primes are guaranteed to occur at least twice. Relations containing a particular large prime are multiplied together pairwise (i.e. multiplying the residues and merging the two lists of primes).
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