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hhh 2007-05-30 06:48

I am currently sieving prime n up to 25M; with multisieve, I am at p=25M and about to change to the next gear, i.e. gcwsieve. From now on, progress should be very fast.

I will post the factors for the 5M-10M range later today, the only ones missing are those from the last not yet assigned P-1-ranges.

More information is to come; I need breakfast before;-o

ATH 2007-05-30 12:26

ok, I won't sieve prime n's then, but continue with my big range. I might expand to 25M as well then when I hit 5G for 0-10M.

hhh 2007-05-31 10:41

1 Attachment(s)
As promised (a little late, though) the factors found so far. The content is in no sense beautiful, the best thing to do is probably to export everything out of the spreadsheet. I hope you can use the data in a way or another. Yours H.

ATH 2007-05-31 22:31

Thanks alot for those factors.

After cleaning it up and removing duplicates and only keep lowest when 2 factors to same n, I came up with factors for 1,499 cullen numbers:


and 2 factors that didn't check out:

19698213427 is not a factor of 1624241*2^1624241+1
8241190129247 is not a factor of 1638701*2^1638701+1

ATH 2007-05-31 22:59

Nevermind it was a typo in database.xls altering the n-value:

19698213427 is a factor of 1632341*2^1632341+1 (instead of 1624241)
8241190129247 is a factor of 1638107*2^1638107+1 (instead of 1638701)

So the total is still 1,499 factors.

ATH 2007-07-07 13:02

I expanded my sieving to 1 ≤ n ≤ 25M and sieved up to 5.4 G with a total of 24.221.687 factors found (including all those you found in this project) + the 14 known primes leaving 778.299 (3.15%) unfactored.

Factors for 1≤n≤10M: [URL=""][/URL] (35 Mb)
Factors for 10M≤n≤25M: [URL=""][/URL] (51 Mb)

Sieve file in ABC format with remaining 778.299 unfactored: [URL=""][/URL] (2 Mb)

I'm taking a break awhile from sieving cullen's plus I'm going on vacation :) Good luck on the project.

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