20171218, 17:26  #386 
"Nuri, the dragon :P"
Jul 2016
Good old Germany
2E2_{16} Posts 
A few days ago PG found the mega prime
Code:
273809*2^89324161 The prime is 2,688,931 digits long. The official letter 
20171228, 09:52  #387 
May 2004
FRANCE
2^{4}×5×7 Posts 
Sierpinski odd n's testing
Hi,
k=9267 is now tested up to n = 8,806,303 (2,650,966 decimal digits) no prime, continuing... Best Regards, Jean 
20180106, 09:53  #388  
"Nuri, the dragon :P"
Jul 2016
Good old Germany
2×3^{2}×41 Posts 
Quote:
The calc prime results are looking good. Code:
using base 2, sieve depth 50000000, and reading 781255 candidates from t17_b2_k9519.npg expected # of primes: 1.7263706830854946 odds of at least one prime: 82.20709997186222% (or, in other words) 1 in 1.2164399429517392 chance of at least one prime on average, 1 in 452541.8600156512 candidates should be prime After the file is done, around 03/2018, I´ll go ahead and start some testing. Everyone is welcomed to support. 

20180106, 21:09  #389  
May 2007
Kansas; USA
11×929 Posts 
Quote:
Are you sieving only the even n? If not, you are outside of the scope of the project. The easiest way to accomplish sieving even n only for 9519*2^n1 n=2^24 to n=25M is to sieve base 4 instead for half the nrange; that is sieve 9519*4^n1 for n=2^12 to n=12.5M. My guess is that at most, there is a 20% chance of prime for even n for n=2^2425M. Are you certain that you really want to do this? It would be extremely low priority on our sieving needs at this point. Last fiddled with by gd_barnes on 20180106 at 21:19 

20180106, 22:32  #390  
"Nuri, the dragon :P"
Jul 2016
Good old Germany
2×3^{2}×41 Posts 
Quote:
But it looks like the number of expected primes was wrong, so I´m dropping this effort. 

20180107, 06:08  #391  
May 2007
Kansas; USA
11·929 Posts 
Quote:
The number of expected primes that you came up with is likely correct for ALL n but that is not what CRUS needs. You would need to sieve only even n. Sieving 9519*4^n1 accomplishes that. Plenty of primes have already been found for base 2 k=9519 odd n. 9519*2^11, 9519*2^111, and 9519*2^151 are all prime and those are just the smallest 3 primes. Regardless the effort is apparently not what you expected so it's best to drop it at this point. Few people want to run tests that take more than 1 day each. Last fiddled with by gd_barnes on 20180107 at 06:10 

20180116, 17:13  #392 
Jun 2009
2·5·67 Posts 

20180116, 18:54  #393 
"Nuri, the dragon :P"
Jul 2016
Good old Germany
2·3^{2}·41 Posts 

20180116, 20:37  #394 
"Curtis"
Feb 2005
Riverside, CA
2×5×19×23 Posts 
Looks like fun I'll donate at least a haswellcoremonth to LLR when the sieve file is ready.

20180116, 20:47  #395 
Jun 2009
29E_{16} Posts 

20180116, 22:28  #396  
"Nuri, the dragon :P"
Jul 2016
Good old Germany
1011100010_{2} Posts 
Quote:
You might also ask PG, so far I know they did some sieve files with way deeper P´s than yoyo@home would possibly do. 

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