20120422, 21:34  #56  
Just call me Henry
"David"
Sep 2007
Liverpool (GMT/BST)
2·5·613 Posts 
Quote:
I will try the c code now. 

20120425, 17:28  #57 
Just call me Henry
"David"
Sep 2007
Liverpool (GMT/BST)
13762_{8} Posts 
The c program is incredibly fast compared with the pacsal. It does use more memory but that should be livable with.
I just sieved 0100T for 7tuples upto 2G in about 4 hours. This used about 4Gb of memory but the testing was done in <5 minutes so I don't need to sieve so far. I am not sure the numbers in post #38 are correct. I searched ~1/7 of the range and the best I found was a 4tuple. I will do 100T200T this evening. Not decided what sieve bound I will use but much smaller. edit: How much speed am I losing by doing two 100T chunks rather than one 200T? Last fiddled with by henryzz on 20120425 at 18:00 
20120425, 18:32  #58  
"Robert Gerbicz"
Oct 2005
Hungary
3×5×109 Posts 
Quote:
For 7 tuple biwema said that "Range per one tuple: 730000 T" at 301 digits (though not checked that these times are correct or not). So you searched 1/7000 of that range. 

20120425, 19:25  #59 
Just call me Henry
"David"
Sep 2007
Liverpool (GMT/BST)
1011111110010_{2} Posts 

20120425, 21:59  #60 
Just call me Henry
"David"
Sep 2007
Liverpool (GMT/BST)
2×5×613 Posts 
Running 100T200T upto 0.5G took 5/6 the time of upto 2G for 0T100T and used only half the memory(2GB). The sieve file is 1.6x the size but testing is super quick at this size.
I found one more quad in 100T200T 
20120427, 08:40  #61 
"Vincent"
Apr 2010
Over the rainbow
2×31×47 Posts 
so... testing k 520 T for n=10011 have given me 2 3tuple so far
5364983132499*2^10011+1 5364983132499*2^100111  Twin  5364983132499*2^10011+5  3Tuple  and 14575260764109*2^10011+1 14575260764109*2^100111  Twin  14575260764109*2^10011+5  3Tuple  I hope I will get at least 2 more 
20120427, 11:43  #62  
Mar 2004
17D_{16} Posts 
Quote:
On average you might expect 3 3tuple per 10 T range. Im am sorry that i did not yet answer about my calculations. I just was busy. I try to do my best and give a detailed answer this weekend. 

20120427, 12:29  #63 
"Vincent"
Apr 2010
Over the rainbow
2·31·47 Posts 
32 M value sieved to 1G (with the quad sieve in this thread) to start, split in two, one half sieved to 125B o( 7220422 tested value) and 800B for the second half( 3M700k value left)
In the first half , 284 twin 1 truple. i havent finished testing the second half Last fiddled with by firejuggler on 20120427 at 12:55 
20120427, 16:21  #64 
Just call me Henry
"David"
Sep 2007
Liverpool (GMT/BST)
1011111110010_{2} Posts 
I am currently running 4 different versions of gsieve on a quad in parallel to test what sieve depth is best for 7tuples. I am running 250M, 125M, 50M, and 10M.
At half way through 10M has about twice as many candidates as 50M but as testing is so fast(0.0014 per test) at n=1000 so there is still a saving. 125M isn't too far behind but 250M hasn't even reached half way yet(the other 3 have reached 3/4 as I type). 10M should complete in about 80 minutes. This is down from 4 hours it took to got to 2G. Next I will fiddle with bound_small_primes. Last fiddled with by henryzz on 20120427 at 16:23 
20120427, 18:02  #65 
Just call me Henry
"David"
Sep 2007
Liverpool (GMT/BST)
13762_{8} Posts 
I spoke too soon saying 80 minutes was good. Increasing bound_small_primes to 13 took 35 minutes to complete and 17 took 22. 19 looks like it will take about 30.
I don't think there are any huge improvments left but I will fiddle with sieve_len and hash_bits. 
20120427, 18:28  #66  
Jun 2009
1010111100_{2} Posts 
Quote:
If I understood Robert correctly, you need a very large search range for bound_small_primes=19 to be efficient. I'm really curious what sieve_len will do to performance and memory usage. 

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