Octoproths

[robert44444uk]

I didn't know there was an upper limit, I just do it!

I am using version 2.81, and I set max Mb ram to 100.0

I ran n=71 last night - only one value survived the sieve and the first pfgw run, and that turned out to be composite for k.2^71-1

So Anx1's record still stands.

Regards

Robert

[Templus]

I tried n=81 yesterday for 2<k<2^32. As far as I know, there is no upperbound, since NewPGen splits this large range into smaller pieces (dependent on the max. RAM assigned?) and sieves these ranges until 1 billion.

As I said, I tested n=81 yesterday with OpenPFGW and there was no complete set in the log-file. I still have the sieve file, so anyone who wishes to redo it can ask me for the sieve-file. I uploaded the sieve file on http://www.diamondvalley.nl/octoproth

I'm taking 82+....sieving until k=2^32 takes about 1,5 or 2 hours for me. Testing these numbers for PRP is done in less than a minute (small n)

[ltd]

Are n=74,75,76 free ?

I would like to test them.

Lars

[axn]

Originally Posted by robert44444uk

I didn't know there was an upper limit, I just do it!

I am using version 2.81, and I set max Mb ram to 100.0

Hmmm.... Must be the version. I am using 2.82. If I put k higher than 2^32-1 it just wont budge :

But on the plus side, I went and wrote up a sieve program for myself. The initial results are *very* encouraging. I sieve all 8 forms simultaneously.

Some statistics. After sieveing for k < 10^10, with p < 1M, I get just 90 (count'em) candidates

[axn]

And the winner is:

k=61574201535, n=80

[robert44444uk]

Originally Posted by ltd

Are n=74,75,76 free ?

I would like to test them.

Lars

You might want to try a bit higher, given the latest record. This is addictive!!

Regards

Robert Smith

[ltd]

OK i take 100,101,102

Lars

[axn]

Another one for n = 80

k = 632893190475 !!

[axn]

n = 80 finished for k < 10^12. On to bigger n's

[ltd]

Originally Posted by axn1

Hmmm.... Must be the version. I am using 2.82. If I put k higher than 2^32-1 it just wont budge :

Strange i use 2.82 also and i have no problems sieving >2^32.

[axn]

Originally Posted by ltd

Strange i use 2.82 also and i have no problems sieving >2^32.

D'oh! It looks like I've run into a bug in NewPGen. Try putting kmax = 4294967296 (2^32). It doesnt do anything. If you put any other number in there (including really big numbers), it springs into action!

Well, anyway, my new sieve is a lot better suited for this search.