[QUOTE=bcp19;307500]
Just because an exponent is 'the lowest unverified' so far, does that statistically make it more likely to be a prime? Why is it considered a 'plum'?[/QUOTE]

Yes. Probability of being prime is inversely proportional to the exponent.
Time taken to LL is proportional to exponent[SUP]2[/SUP].
So probability/year of finding a prime is proportional to 1/exponent[SUP]3[/SUP].

Humble toilers such as myself like these plums, and resent them being reserved for Chalsall's Chums.

Look after the waveFRONT speed, and let the tail look after itself.

If Primenet can't exploit GPUs properly yet, it should retire all the hoarded TF assignments >53M.

D

[QUOTE=axn;307543]Nothing much. With that, I'll shut up.[/QUOTE]
Please don't.
I (for one) respect your contributions immensely.
You need a thicker skin to resist the morons around here.

David

[QUOTE=axn;307543]Nothing much. With that, I'll shut up.[/QUOTE]

Some of your erato.cu optimizations are also in my GPU sieving code. I guess that also makes you one of the two dozen or so that have contributed actual working code - thanks! PM me, if you'd like a copy of the new sieve code to see if you can find some more micro-optimizations.

[QUOTE=Uncwilly;302628]All exponents below [COLOR="Blue"]24,212,801[/COLOR] have been tested and double-checked.
All exponents below [COLOR="DarkRed"]38,195,891[/COLOR] have been tested at least once.

Countdown to testing all exponents below M(42643801) once: 28
Countdown to testing all exponents below M(43112609) once: 35

Countdown to proving M([COLOR="DarkOrange"]25964951[/COLOR]) is the [COLOR="darkorange"]42[/COLOR]nd Mersenne Prime: 185
Countdown to proving M([COLOR="Purple"]30402457[/COLOR]) is the [COLOR="Purple"]43[/COLOR]rd Mersenne Prime: 35,330[/QUOTE]
All exponents below [COLOR="Blue"]24,212,801[/COLOR] have been tested and double-checked.
All exponents below [COLOR="DarkSlateGray"]41,060,057[/COLOR] have been tested at least once.

Countdown to testing all exponents below M(42643801) once: 13
Countdown to testing all exponents below M(43112609) once: 18

Countdown to proving M([COLOR="DarkOrange"]25964951[/COLOR]) is the [COLOR="darkorange"]42[/COLOR]nd Mersenne Prime: 70
Countdown to proving M([COLOR="Purple"]30402457[/COLOR]) is the [COLOR="Purple"]43[/COLOR]rd Mersenne Prime: 28,626

It looks like 3 of these milestones will get retired by the end of 2012.

GIMPS is close to testing all Mersenne numbers up to 2^43112609-1,
which will eventually prove that M47* = M47.

As long as we have no proof that the Mersenne Primes are infinite in
number, continuing the search beyond any given limit such as M47 is
of course interesting but unbounded.

Hence my question: is there any way to measure the probability that
M47 is the last Mersenne Prime?

A few observations:

1. The pfrakes exponent that chalsall linked to above is most likely the same user testing it twice. I suspect this was because the first-time test was done in v4 and the second time test done in v5 and v5 does not remember the v4 IDs for checking if the same user returned two LLs for the same test. Also, George has a second check - the shift count - and if both results are submitted using Prime95 it becomes very hard - if not impossible - to fake these.

2. George's reply on what GPU72 has done for us is pretty much to the point. I would just like to point out that I am one of those who runs his own script periodically to get plum DCs and I found that I was able to get what I wanted even when GPU72 was grabbing exponents. I do think George's idea of leaving 1 mod 4 or even just 1 mod 4n where n>1 exponents for non-GPU72 users is a good idea.

3. My count of exponents between 25-26M is now 23/72. So I am keeping with the pace.

[QUOTE=sonjohan;307214]I get it that poaching is not supposed to happen, but how can we advance the milestones faster?
One of the 2 DC left in the 24M range is over 1 year old.
How can you see whether progress is being made on these or not?[/QUOTE]
I've been tracking 24-26M assignments for some time, and the two you mention have the following stats:
xx,xxx,801 - 10.90% on 5/9, 11.00% on 8/12
xx,xxx,607 - 61.20% on 4/8, 61.20% on 5/7, reassigned on 5/9, no progress to date.

[QUOTE=Prime95;307571].[/QUOTE]

Since you are following this thead, I want to ask: Do you plan to implement any assignment recycling rules like these or similar?: [URL="http://www.mersenneforum.org/showpost.php?p=222164&postcount=443"]http://www.mersenneforum.org/showpost.php?p=222164&postcount=443[/URL]

I think it would be nice with something preventing assignments for getting stuck and running 2+ years with little progress.

[QUOTE=ATH;307748]Since you are following this thead, I want to ask: Do you plan to implement any assignment recycling rules like these or similar?[/QUOTE]

At the time I proposed that, there was a fair amount of opposition so I elected to not implement any changes.

[QUOTE=Prime95;307757]At the time I proposed that, there was a fair amount of opposition so I elected to not implement any changes.[/QUOTE]

Please consider this post the second vote for implement those rules.

[QUOTE=Dubslow;307758]Please consider this post the second vote for implement those rules.[/QUOTE]

Third.