Thread: 5000 < k < 6000
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Old 2009-07-30, 01:00   #9
Mar 2004

3·11 Posts

Originally Posted by kar_bon View Post
another point to check and consider is the sieve depth!

i've done some tests via LLRnet and there'e my get a candidate with n-value by random.
so i had a pair with n=970k.

as you mentioned, you sieved to only 3T or a bit higher, that's ways too low for a n-range upto n=1M. perhpaps Gary can tell you a better value but i think a sieve depth to 50T or 100T would be minimum before testing n-values over 900k!
it's a new idea to present test-candidates by random but there're aspects against doing so:

1. the sieve depth has to be quite high
2. the verification of the whole range (k=5000-6000 and n=75k-1000k) is a tremendous work: check if all candidates tested
3. presenting the results (which k got which prime n's) like the table would be open until all tests are done, and this could take years!

what about sieving and testing smaller ranges in n (say 100k-ranges) , and while testing per LLRnet, the sieving for the next range could be done higher!

PS: the html-version of the page contains a link to itself!? should this be the link to php-version?
the html-version shows better the completed range as [...]!
another hint: it would be easier to split the column with 'n tested (prime)' so you could better summarize both columns (for example copying the page and inserting in Ex*el!)
You are right about the sieving, but if we break it off into chunks, then we are just doing the test the "old way"

100T may be a tad high for a range of this size, but it definitely has quite a bit more sieving to go. Which will be done concurrently. I dont think the numbers are big enough (n = 999,999 would take <15 min to test on a modern core) to justify putting everything on hold for the months that it would take to sieve deep enough.

The html page shouldn't be accessed. it is old. Did i link to it somewhere? Sorry. Originally the php page was very slow to load due to slopy database calls, so there was a link to the html static page for speed......which was just a copy (link included) of the php. Now that the php is fast enough, that isnt necessary and will be deleted.

I understand your point about using excel, but the page is dynamically generated, so I can split the columns on the fly pretty easily. I dont really think that a column just for number of primes over 50,000 is necessary, in fact I wasnt going to list is at all, because there already is a column listing the primes. If one really wanted to know how many there were, they could count. But if enough people deem it necessary, I suppose #p>50,000 could get its own column.

The primes are a subset of the results, so for now, i think it is ok for them to stay that way.
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