20130716, 08:24  #518 
Feb 2003
2^{7}×3×5 Posts 

20130716, 13:01  #519 
Jun 2003
Suva, Fiji
2^{3}×3×5×17 Posts 
186!!!!!
Good news Thomas11 for your Sierpinski candidate and very happy to see the Riesel powering along.
This candidate has another to report with all n checked to 187965 184? 190958 185? 193804 186?? 255530 
20130718, 09:36  #520 
Feb 2003
2^{7}×3×5 Posts 
Meanwhile I completed the interval n=250300k and found another one:
184? 190958 185? 193804 186?? 255530 187?? 294807 I will continue from n=300k. 
20130719, 07:47  #521 
Feb 2003
780_{16} Posts 
188!!!
We are getting close to 190 primes:
184? 190958 185? 193804 186?? 255530 187?? 294807 188?? 318934 
20130719, 08:08  #522  
Jun 2003
Suva, Fiji
2^{3}·3·5·17 Posts 
189 actually
Quote:
184 190958 185 193804 186? 210616 187?? 255530 188?? 294807 189?? 318934 [/QUOTE] 

20130719, 16:02  #523 
Jun 2003
Suva, Fiji
2040_{10} Posts 
190 up!
Another found before 200K. I have completed up to 197962
186 197942 187? 210616 188? 255530 189? 294807 190? 318934 
20130721, 11:12  #524 
Feb 2003
11110000000_{2} Posts 
192!!!
I found a nice double:
187? 210616 188? 255530 189? 294807 190? 318934 191? 334623 192? 334645 
20130722, 09:37  #525 
Jun 2003
Suva, Fiji
2^{3}×3×5×17 Posts 

20130724, 14:42  #526 
Jun 2003
Suva, Fiji
2^{3}·3·5·17 Posts 
Oh dear, it has gone quiet around here, which means maybe we have a gap on its way.
I'm up to n=218969 with no further primes, so 187 210616 is confirmed. Interestingly, the candidate has no twin primes to date, only 6 Sophie Germain pairs and no longer Cunningham chains. 
20130725, 15:25  #527 
Jun 2003
Suva, Fiji
2^{3}·3·5·17 Posts 
Still no new prime, up to 219623, but with empty chunks (220000226470) and (230000232660) done.
I thought I would plot x=nth prime versus y=ln2(ln2(k*2^n1)) and see what I got. As expected a very linear relationship and what's more this suggests the 200th prime at about n=475,000 unless I did the maths wrong. Actually, I think it will be greater than this value. 
20130725, 16:26  #528 
Feb 2003
2^{7}×3×5 Posts 
The plot is indeed very linear. I did similar plots for some of my Sierpinski candidates, but they are typically more "scattered".
But let me add another prime to the series: 193? 363020 The interval n=300350k is fully tested now, continuing to 400k. 
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