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Citrix 2007-01-23 08:10

[QUOTE=paulunderwood;96826]We are at nearly 3.1 million bit tests and it is not the end of January yet :geek: That's about 80% towards a million digits. We are due a prime, but, fingers crossed, that prime will occur at just over a million digits :wink: But who knows? [URL=""]Join us and chance your arm[/URL].[/QUOTE]

IF you find a million digit prime soon (which I hope you do), will you still continue to LLR to 5 M?

paulunderwood 2007-01-23 16:22

[QUOTE]IF you find a million digit prime soon (which I hope you do), will you still continue to LLR to 5 M?[/QUOTE]

Hardly, No. Personally, the main goal is a 1 million plus digit prime. The effort would have to be redoubled to find the following prime, most likely and that could be greater than 5M bits :cry: So it just a final push now. Help us :smile:

Citrix 2007-01-23 21:15

Will help soon! (As soon as I can free up a computer).

paulunderwood 2007-02-12 12:01

Thomas wrote:
[QUOTE](Just as a note: The next FFT length change is at n=3121158. Tests will take about 20% longer above that n-value.)[/QUOTE]

Thanks for the reminder. This new FFT size will last until n=3719191, i.e. for the rest of the year. 32-bit athlons can continue at the old length until n=3171158.

That is now 5 hours per test on a Pentium 4 at 3 GHz. Quicker on a Core 2 Duo.

Thomas11 2007-02-12 13:55

[QUOTE=paulunderwood;98269]32-bit athlons can continue at the old length until n=3171158.[/QUOTE]

The above holds for version 3.5 (or below) of LLR. For LLR 3.6 and higher the 32bit Athlons will use the old length until n=3180158.

The make the things even more complicated: We found LLR 3.5 slightly faster than the newer versions on the Athlons (a fraction of a percent). So the Athlon testers might use version 3.5 up to n=3171158 and then switch to version 3.6/3.6.2/3.7...

paulunderwood 2007-02-26 19:12

Welcome back James!

I have asked Xyzzy to upload the next set of LLR input files, covering 3.15M to 3.3M bits, which will take us very close to 1 million digits (3.32M).

Tests take nearly 6 hours each on a Pentium 4 at 2.66GHz. An average file will take 2 weeks -- with 58 numbers. This will be the case until about 3.7M bits.

Thanks to Geoff for the new sieve, which Carlos and Thomas used to get the least divisor up to 245 trillion.

We are due to find a prime :smile:

If we find a prime now it will be 12th largest known.

Good luck all :grin:

SB2 2007-02-27 01:00

Thanks Paul, it's good to be back.

paulunderwood 2007-03-22 01:10

I have just completed the last sub-3 million bit 321 candidate. Great work people. :tu:

Our next goal is to reach 1 million decimal digits by the end of May. After reaching this mile stone I hope we find another prime quicky.

In the long term, it would be great to get to 3.6 million by the end of this year and then a 4 million bits target for the end of 2008 will be easily attainable.

Our next prime is due at 4.1 million bits. However we do not know where it actually is. It could be much smaller or much larger.

Good luck all with finding our next 321 prime! :wink:

paulunderwood 2007-05-03 10:05

It looks as though we will miss the end-of-May target for all candidates below one million digits to be booked out, but we should easily get there by the end of June :smile:

For [I]all[/I] 0<n<3M, Thomas and I have been testing pre-project candidates or those missing numbers due to human error and those tested with PRP/PFGW, such that by the end of May we will have, uniformly, a divisor or a LLR residue :flex:

My effort will slow down in the hot summer months, but hopefully with people being interested in finding a mega-prime, the 3.6M goal is still on for the end of this year.

Anyone who wants to make a start on mega-prime tests should email me.

Here are some relevant project links:
[URL=""]Current status[/URL]
[URL=""]Prime Pages Bio for 321[/URL]
[URL=""]Contributor Statistics[/URL]


paulunderwood 2007-06-02 21:33

Thanks to Xyzzy for uploading the latest 321 input files ready for LLR crunching, covering from n=3.3M to 3.45M. :tu:

We are also grateful to Thomas for further sieving these to 271.2 trillion. :bow:

This batch will take us over 1 million decimal digits (3.32M) :w00t:

Grab yourself some and maybe you will find a mega-prime :love:

Also we have covered all n from 0 to 3M with a factor or an LLR residue. After some more analysis of errors, we will make all public...

paulunderwood 2007-07-11 09:34

We are now testing candidates for a prime number with over 1 million digits, a so called mega-prime :w00t:

Thanks to all who have helped over the last 4 years to get us here.

Join us!

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