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Old 2005-02-15, 00:12   #8
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"Richard B. Woods"
Aug 2002
Wisconsin USA

22·3·641 Posts

Originally Posted by Peter Nelson
Now what was still confusing me was then machines that were doing TF. Clearly the field is used to hold something else in this case, but what.

Someone said there was a table of values (I've observed values from 5 to 11) and their meaning for interpretation during factoring. Does anyone know where?
During TF, the "current iteration" field on the report shows which of 16 passes the TF was currently doing on its current bit level when the program reported progress. The possible range is either 0-15 or 1-16 -- I forget which.

For maximum speed, on each bit level TF tests factors in each possible congruence class mod 120 separately. That is, when testing factors between 2^63 and 2^64, TF first tries all factors that are congruent to 1 mod 120 (first pass), then all factors that are 7 mod 120 (second pass), then 17 mod 120 (third pass), and so on. (11 mod 120, 13 mod 120, etc. are skipped because a factor must also be +- 1 mod 8.) When the program reports progress to PrimeNet, it sends the TF pass number as the "current iteration".
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