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

[Lennart]

220k-230k Complete No primes

Lennart

[gd_barnes]

Holy cow. Fast moving drive!

Max, Thanks for posting more files. I was going to drop to 3K files at n=220K. I suppose that is not necessary now.

Just to let everyone know: An n=5K file at n=280K could take ~1-2 CPU weeks. If you need a smaller file, feel free to reserve part of one. A personal PRPnet server running several cores on it is probably the best way to process one or more of the files.

It looks like Karsten took all the primes before releasing this base. lol


Gary

[henryzz]

Using pr_prob it seems you can expect a prime every ~5100 tests at n=150k and ~8600 at n=250k.
I didnt do exact conversions for digits in base 6 to digits in base 2 hence the ~s.
You are not lacking in primes found.

[Flatlander]

Taking 250-255.

[Lennart]

230k-250k Complete No primes


Taking 255k-260k............................!!

[mdettweiler]

185K-190K complete, no primes. Results attached.

Taking 260K-265K.

[Lennart]

255k-260k Complete No primes

[kar_bon]

it's seems i have to participate to find the next prime, heh?

[gd_barnes]

Originally Posted by henryzz

Using pr_prob it seems you can expect a prime every ~5100 tests at n=150k and ~8600 at n=250k.
I didnt do exact conversions for digits in base 6 to digits in base 2 hence the ~s.
You are not lacking in primes found.

I ran it through my "odds of prime" spreadsheet, which allows the conversion to other bases. Here is what I have:

n=150K; 1 in 5129
n=175K; 1 in 5984
n=200K; 1 in 6839
n=225K; 1 in 7694
n=250K; 1 in 8548
n=275K; 1 in 9403
n=300K; 1 in 10258


It looks like you DID do some sort of conversion to base 6 because your odds are very close to mine. Changing the above to base 2 would have made a much better chance of prime at each level.

Below is what we have completed so far and the expected # of primes at each n-range level. To make it easier, I just took the avg. # of pairs that should be at each range (989 per each n=10K range) and the average n-range. Technically you should use the exponential avg. but the ranges are small enough that's it not too far off. In other words, the estimate should be a few hundredths of a prime higher.

150K-170K; 0.36 primes
175K-190K; 0.24 primes
200K-215K; 0.21 primes
220K-250K; 0.37 primes
255K-260K; 0.06 primes

Total: 1.24 primes

So it looks like we are "lacking" on primes for the range that we have searched so far. Alas, it's only one prime. I do hope we get at least 1 by n=300K. If not, my estimate of finding them all by n=~10M will have to increase to n=~12M-15M.

We still have some gaps left to fill in yet but the highest percentage increase in n-value between primes so far has been 49.8%...from n=66262 to n=99609. To top that, we'd have to not find a prime up to n>214570. But it's to be expected that the percentage will keep getting larger as we search higher since there are less k's to find a prime for.


Gary

[gd_barnes]

Originally Posted by kar_bon

it's seems i have to participate to find the next prime, heh?

Yes! Bring on the Riesel base 6 prime finder!

[Lennart]

Taking 265K-270K.

Lennart