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1) Message boards : News : New SR5 Mega Prime Found! (Message 72301)
Posted 2509 days ago by John
Congrats and all, but why are these just now being reported, if I may ask?
2) Message boards : General discussion : Cunningham Chain sieving (Message 70782)
Posted 2576 days ago by John
I just started looking at Cunningham Chain records on , and was wondering on file preparation for testing for a certain length. Lets say I was looking for a "2nd kind" chain of length=5... could I sieve, say, 100 consecutive n-values for 1<k<1e9 for k*2^n+1 (odds only of course), then merge all the files and sort by k somehow so I could LLR test only those k values that have 5 or more consecutive n's without having to go through the file myself (taking hours, I'm sure)? If so, how would you suggest doing so?
3) Message boards : Proth Prime Search : Testing Proth Primes for Fermat Divisibility (Message 69793)
Posted 2607 days ago by John
What is the best way to test, say, a .txt output file from LLR to see if any of the numbers in the file divide a Fermat number? I.e. I'm running n=70-100k for k=30k-40k, and wanting to see if any of the primes I've found are Fermat divisors, but they aren't big enough for Top-5000, so I can't rely on the site to test divisibility for me. Should I use PFGW with the -gxo flag, or what?
Thanks in advance!
4) Message boards : News : Equinox challenge 17 March - 22 March 11:02 UTC (Message 63696)
Posted 2810 days ago by John
Yup. Anyway breaking news: I've found my first prime!

What's the expected % of tests to be prime for the challenge?
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