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Old 2007-08-28, 07:30  
gd_barnes
 
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May 2007
Kansas; USA

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Default 57 low-weights for k=200K-1M missing & addl primes

Karsten,

I've held off waiting on a response from SB2 for long enough now. I posted 3 messages in this thread and sent him a PM over a month ago asking for additional information, all with no response. So it's time for me to post this large verification effort that I did on low-weight k's. It will give everyone a lot of good information.

See the attached list for missing and additional low-weight primes to post. There were 6 'truly missing' primes. What this does is that it gives us at least one prime for every k < 509203 that is listed on our summary site and is not being searched by Riesel-sieve. That and double-checking for low primes were my main objectives of the effort.

All needed details are in the attachment but here is a synopsis of my thinking when doing testing:
1. All low-weight k's for 200K < k < 1M were tested up to n=100K with a few exceptions that already had several primes.
2. If no primes were found for a k in #1, then it was tested up to n=300K.
3. If prior testing had already been done for 100K < n < 375K, then I double-checked the entire testing range and tested a little further.

A secondary objective of the effort was to find very composite k's > 509203 that would be interesting for others to search for larger primes. I found 9 k's with Nash weight > 0 where 509203 < k < 1M had no primes up to at least n=300K. I call these "quasi Riesel #'s". For everyone's prime-searching pleasure, I'll list them right here.

low-weight k's for 509203 < k < 1M with Nash weight > 0 that have no primes for n <= 300K:
612509
671413
685183
686711
700057
780427
844559
963643
981493

5 of the 9 k's above are unreserved and the other 4 are showing reserved by SB2, but I don't think anyone really knows for sure. 3 of those 4 show 'sieved to 2000K ready to test' over 6 weeks ago but what does that really mean? Is he going to post the sieve file for others to test or is he going to test them himself? The other one shows "I have stated sieving" over 5 MONTHS ago! But no follow-up was ever given.

If anyone can get a hold of SB2, please let him know that we badly need a status update from him.

The attachment is in an Excel spreadsheet. Let me know if you have any problems reading it.


Gary
Attached Files
File Type: zip low-weight-200K-1000K-000K-375K-1 testing.zip (3.7 KB, 146 views)

Last fiddled with by gd_barnes on 2007-08-28 at 07:38
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