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Old 2009-03-07, 12:02   #276
KEP
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Sierpinski base 63 is at n=1000 with a total of 240131 k's remaining, sieving has just begun on 1 core and within the next 10 days the remaining half will be begun sieved on the next availeable core

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Old 2009-03-08, 07:56   #277
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Quote:
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Sierpinski base 63 is at n=1000 with a total of 240131 k's remaining, sieving has just begun on 1 core and within the next 10 days the remaining half will be begun sieved on the next availeable core

KEP

Cool. Now the question is: Can you get it down to < 10,000 k's remaining? That is the limit of what I have said I would show on the pages.

I did make an exception for Chris on one with 14,000+ k's remainin so I'll make a similar exception here and show as many as 15,000 k's remaining for base 63. Interestingly, that might actually be possible by n=25K if you have a reduction of 50% for every doubling of the n-range. But as I recall, the reduction percentage isn't that high for base 63. I suspect that it would need to be tested to n=50K or higher, which would likely be several CPU decades of work.


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Old 2009-03-08, 10:49   #278
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Originally Posted by gd_barnes View Post
Cool. Now the question is: Can you get it down to < 10,000 k's remaining? That is the limit of what I have said I would show on the pages.

I did make an exception for Chris on one with 14,000+ k's remainin so I'll make a similar exception here and show as many as 15,000 k's remaining for base 63. Interestingly, that might actually be possible by n=25K if you have a reduction of 50% for every doubling of the n-range. But as I recall, the reduction percentage isn't that high for base 63. I suspect that it would need to be tested to n=50K or higher, which would likely be several CPU decades of work.


Gary
I'll see what can be done, however I will not give any promises of testing beyond n=25K, and sincerely I really don't think that it will be nescessary to test beyond n=25K in order to get Sierpinski base 63 below 15000 k's, even if the 50% reduction should not be accurate

I'm btw going to sieve untill it takes ~120 seconds to remove 1 k/n pair, before start crunching. At p=53 million, the removal rate is about 150 k/n pairs each second, with ~249,225,000 pairs remaining in the sieve file

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Old 2009-03-09, 13:06   #279
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Default Riesel Base 58

25272*58^13090-1
50072*58^13250-1
98172*58^13259-1
19854*58^13287-1
4188*58^13378-1
72038*58^13430-1
15747*58^13650-1
21783*58^13793-1
44697*58^13920-1
71432*58^13974-1
32685*58^13992-1

Completed to 14000 and continuing
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Old 2009-03-09, 21:48   #280
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Quote:
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I'll see what can be done, however I will not give any promises of testing beyond n=25K, and sincerely I really don't think that it will be nescessary to test beyond n=25K in order to get Sierpinski base 63 below 15000 k's, even if the 50% reduction should not be accurate

I'm btw going to sieve untill it takes ~120 seconds to remove 1 k/n pair, before start crunching. At p=53 million, the removal rate is about 150 k/n pairs each second, with ~249,225,000 pairs remaining in the sieve file

KEP
Holy smokes! All that I can say is: Good luck! An ABCD version of that file must be several hundred MB.

If you were able to get this base to n=25K, I would be amazed. For me, it would come down to the boredom factor. To do it, I'd just have to put several quads off in a corner somewhere and let them crunch for months or years without even looking at them other than to make sure they are still running and checking their status every couple of weeks.

BTW, if you are going to sieve until it takes 120 secs. to remove a pair, since your current rate is 150 pairs/sec. and you are at P=53G, my estimate of your sieve depth would be:
150 * 120 * 53G = 954T or almost 1 quadrillion or 10^15!!

As difficult as it will be with a monsterous sieve file, you might want to break off some of the lower n-ranges and do primality testing on them before sieving so far. Since you'll find a lot of primes at the lower n-ranges, you'll be able to remove a lot of k's from the sieve file, which will make it a little more manageable in size. As an example: You might consider doing testing on n=1000-2500 after sieving to around P=1T. While it technically may not be the most efficient way CPU-wise in the long run, it may take less of your personal time in the long run not having to mess with such a huge file.

We are quite happy to let you do the really "tough" bases.


Gary
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Old 2009-03-10, 00:18   #281
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Holy smokes! All that I can say is: Good luck! An ABCD version of that file must be several hundred MB.

If you were able to get this base to n=25K, I would be amazed. For me, it would come down to the boredom factor. To do it, I'd just have to put several quads off in a corner somewhere and let them crunch for months or years without even looking at them other than to make sure they are still running and checking their status every couple of weeks.

BTW, if you are going to sieve until it takes 120 secs. to remove a pair, since your current rate is 150 pairs/sec. and you are at P=53G, my estimate of your sieve depth would be:
150 * 120 * 53G = 954T or almost 1 quadrillion or 10^15!!

As difficult as it will be with a monsterous sieve file, you might want to break off some of the lower n-ranges and do primality testing on them before sieving so far. Since you'll find a lot of primes at the lower n-ranges, you'll be able to remove a lot of k's from the sieve file, which will make it a little more manageable in size. As an example: You might consider doing testing on n=1000-2500 after sieving to around P=1T. While it technically may not be the most efficient way CPU-wise in the long run, it may take less of your personal time in the long run not having to mess with such a huge file.

We are quite happy to let you do the really "tough" bases.


Gary
1. I'm happy to take the big bases, though I can say with a 100% guarantee that this will be the final base and the final CRUS work I'm ever gonna complete

2. I'm going to sieve the remaining k's from n=1001-25000 on 2 cores. The remaining 2 cores I'll keep busy doing my own Mega-prime project and get that started really good, and then once I feel like there has been sieve deep enough, then I will convert the ABCD files to NewPGen files and start PRP testing on the Dual core and then use the entire Quad on my MegaPrime project.

3. Current ABCD file availeable takes up 1.46 GB of data, and currently ~70 pairs is removed every second :) Leaving 236.6 million pairs remaining in sieve file...

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Old 2009-03-10, 11:20   #282
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Sierp base 75 is complete to n=25K; 5 k's remain; unreserved.

Sierp base 42 is at n=17.5K; 47 k's remain; continuing to n=25K.

Now working on Sierp base 70 to n=25K.
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Old 2009-03-10, 11:32   #283
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Originally Posted by KEP View Post
I'll see what can be done, however I will not give any promises of testing beyond n=25K, and sincerely I really don't think that it will be nescessary to test beyond n=25K in order to get Sierpinski base 63 below 15000 k's, even if the 50% reduction should not be accurate

I'm btw going to sieve untill it takes ~120 seconds to remove 1 k/n pair, before start crunching. At p=53 million, the removal rate is about 150 k/n pairs each second, with ~249,225,000 pairs remaining in the sieve file

KEP

I'm not sure where you got a 50% reduction for base 63. I only used that as the simplest possible example for base 3, which is much more prime than just about any other base. Besides, for base 3, 60% is more accurate.

I found my prior post where I had calculated the approximate percentage reduction for base 63 with each doubling of the n-value. It is about 37%. Therefore, we have:

n=1000; 240131 k's remaining
n=2000; 151283 k's remaining
n=4000; 95308 k's remaining
n=8000; 60044 k's remaining
n=16000; 37828 k's remaining
n=32000; 23831 k's remaining
n=64000; 15014 k's remaining


So...it's looking like you'd need to test it to n>64K to get it down to < 15000 k's remaining. And further: I expect the above to be a little low on the k's remaining because the percentage gradually drops as the n-range gets higher because the remaining k's have a lower average weight as the higher-weight k's get eliminated.

Since this is such a huge base, if you're willing to put in the effort to get it up to at n=10K, perhaps I'll make another exception and show as many as 60000 k's remaining on a web page. It will be a BIG page though! :-)

BTW, it looks like there would be 27000-30000 k's remaining at n=25K.


Gary

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Old 2009-03-10, 15:52   #284
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@ Gary:

It's nice to know that you're willing to make another exception, because I'm sieving to n<=25K and that in it self is a huge task, so it would deffinently be nice not to have commitment all the way to n=25K, since I may eventually like to use my entire Quad for something else

I just guessed the 50%, but if what you're guessing is more accurate, then I guess that you'll deffinently need to publish several thousands more than just the 15,000 k's remaining. But we will see, only time can tell how deep I get to sieve and how high n-value I test, though it's going to be a nice task that I can put on my dual core, since it will not require much attention for a long period of time

Regards

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Old 2009-03-10, 17:08   #285
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why not just have a .txt file with the list of sequences remaining in it
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Old 2009-03-11, 04:42   #286
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Originally Posted by KEP View Post
@ Gary:

It's nice to know that you're willing to make another exception, because I'm sieving to n<=25K and that in it self is a huge task, so it would deffinently be nice not to have commitment all the way to n=25K, since I may eventually like to use my entire Quad for something else

I just guessed the 50%, but if what you're guessing is more accurate, then I guess that you'll deffinently need to publish several thousands more than just the 15,000 k's remaining. But we will see, only time can tell how deep I get to sieve and how high n-value I test, though it's going to be a nice task that I can put on my dual core, since it will not require much attention for a long period of time

Regards

KEP
I'm confused. Several months ago, you guessed 50% based on an example that I gave that was not intended for any specific base. Now you think that I am guessing at 37%. And before the most recent discussion, you continued to use 50% to conclude that you'll be down to 15000 k's remaining at n=25K even after I previously stated 37%.

Have you forgotten this post and this post that contain my previous discussion about this? The ~37% is not a guess. I did actual testing on k<2000 up to n=3200 to get a relatively accurate estimate.

Also, you can look in your own k's remaining and primes. I'm sure it will show that you're not coming in anywhere near 50%. Do some quick and easy math on it and you don't have to guess.

Please stop the guessing. Trust me on this, the percentage reduction will likely come in within 1-5% of 37%.

Quote:
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why not just have a .txt file with the list of sequences remaining in it
It's not the conversion of so many k's to comma-delimited format that takes so long. It's verifying that nothing is missed, k's with algebraic and trivial factors are removed, correct k's that are multiples of the base are removed, etc. and that the # of k's to start with minus the primes found equals the k's remaining. It's that balancing act that takes so long.

Showing all the k's remaining on the pages is trivial compared to balancing stuff for huge conjectures.


Gary

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