Riesel base 6 - team drive #4 - EIGHT OR BUST!

[MyDogBuster]

I would like to reserve from 1.24M-1.25M

Beat me by 4 hours. I'll take 1.25M-1.27M

[Mathew]

Originally Posted by Mathew

I would like to reserve from 1.24M-1.25M

Complete No primes.


Attached are the results

[MyDogBuster]

1.25M-1.27M complete - Nothing found

[MyDogBuster]

1.27M-1.28M complete - nothing found

Results emailed

Oops, forgot to reserve it - sorry

[Mathew]

I would like to reserve from 1.28M-1.30M

[gd_barnes]

Mathew has complete n=1.28M-1.3M. Nothing found.

[Puzzle-Peter]

Reserving 1.3M - 1.4M

[Batalov]

Originally Posted by Puzzle-Peter

Reserving 1.3M - 1.4M

I see that some significant production capacity freed up. :-)

18-20 hours per test, sheesh! I'd say you guys were lucky to find it before b>10^6.

[gd_barnes]

Originally Posted by Batalov

I see that some significant production capacity freed up. :-)

18-20 hours per test, sheesh! I'd say you guys were lucky to find it before b>10^6.

Yep. He just finished R23 for n=700K-1M. That would be some significant production capacity.

[Batalov]

No, for it, I meant the blasted megaprime.

With b ~ 736,000 (e.g. 10^999999+736939), the PRP test takes ~5-6 hrs, but with b ~ 929,000, it takes 18-20 hours (various CPUs), and if they had to go for even higher b values, it would have been worse and worse and worse. I don't know how long it would have taken them to do it without Peter.

[gd_barnes]

Originally Posted by Batalov

No, for it, I meant the blasted megaprime.

With b ~ 736,000 (e.g. 10^999999+736939), the PRP test takes ~5-6 hrs, but with b ~ 929,000, it takes 18-20 hours (various CPUs), and if they had to go for even higher b values, it would have been worse and worse and worse. I don't know how long it would have taken them to do it without Peter.

Now I get it. b is usually used for the base. I believe that it is "c" that you are referring to. As in k*b^n+c or more simply b^n+c in the case of the smallest megaPRP search. c is used in the help guides for the sr(x)sieve series of programs. Perhaps the letters were used a little differently in that search.

I really thought the thread was badly misnamed right from the start and even though it was renamed more than once, I still saw a number of people come there and be confused by it. "Mega" doesn't even necessarily mean million in some contexts. It means 2^20 or 1048576...and it's not a prime search; it's a PRP search...and it's base 10, which isn't clear either (it could have been base 2). The title should have been:

Search for the smallest 1,000,000-digit base 10 PRP

Edit: Here's an interesting side project: Find the smallest 1,000,000-digit base 10 PRIME; that is it must be proven prime. That would be tough...a lot of algebra to come up with a form that factors to 33% that is barely bigger than 10^999999.