Re: [PrimeNumbers] New Record for 13 simultaneous primes
- Dirk Augustin wrote:
> Hi all,Congratulations!
> after sieving through more than 10 trillion candidates to discover a
> new record Cunningham Chain of length 12, I surprisingly found a large
> Cunningham Chain of length 13:
> 1753286498051*2^(n-1)*71#-1, n=1,..,13, (39 digits for n=1)
> This is also a new record for 13 simultaneous primes, where it counts
> with 41 digits (middle member of the chain), improving the old record
> by 8 digits.
Longer than you searched again!
http://hjem.get2net.dk/jka/math/simultprime.htm are updated.
I see you used NewPGen+PFGW like on shorter CC's.
I wonder how practical that is for 12 (and 13!) simultaneous primes.
My sieve using the GMP library for prp'ing has 1 GHz week
expected for a CC12 of this size.
A CC13 would obviously have longer expectation for non-Dirks ;-)
Jens Kruse Andersen