Proth primes with k = 1281979

[bur]

No new primes for n < 3,600,000


Largest n in progress = 3,875,000
# of digits = 1,166,500 (rank: ~ 325)
FFT size = 400k
Avg. time = 4970 s

Smallest n in progress = 3,600,000
# of digits = 1,085,000 (rank: ~ 395)
FFT size = ---k
Avg. time = ---- s


Around July all sieved candidates of n < 4,100,000 should have been tested. I'm not so optimistic anymore that a prime will turn up...

[bur]

Things progressed much faster than I expected, the last batch 4,095e6 < n < 4,100e6 will be assigned to a core today and everything should be finished until June, 10th.


If there will be no prime in these last few numbers, I'll continue by sieving the proth side to higher n and doing LLR on-the-fly depending on sieve/LLR times as LaurV suggested.


According to prime95 I'll be able to continue single-threaded until an FFT size of 640k is reached which will be around n = 5.6e6, which agrees nicely with the 5.3 MB of L3 each core has. I just hope a prime will turn up before testing becomes really slow. I'm set on finding a mega prime for this k though. :D

[bur]

All n < 4,100,000 have been tested, no new primes other than the ones already posted.


Currently I'm sieving in the range of 4,100,000 < n < 10,000,000.

Smallest p-P range in progress: 87E12-107E12
Avg. time per factor: 810 s

Largest p-P range in progress: 310E12-330E12
Avg. time per factor: 3160 s

Remaining candidates: 100,936 / 5,900,000 (1.71%)


Est. time per LLR test of smallest candidate: 5600 s (n = 4,100,014)

[bur]

Quick update, no new primes...


All n < 4,300,000 have been tested.

n < 10,000,000 sieved up to 570E12 (10,000 s / factor)

Approximately 90,000 candidates remain.

Largest LLR-test currently running:
n = 4,450,000
FFT = 448k
6200 s / test
Caldwell entry rank: 290


If the LLR-runtime would increase strictly quadratic, then it'll take to around n = 5,600,000 until an LLR test takes again as long as sieving to eliminate a candidate. As a very rough estimate that should take about 7 months on the 10 core.

And when will the next prime appear? Judging from Primegrid's results on other prime k values it can be a looong time.

[bur]

To keep up with the roughly monthly updates and since it's been one year now since I started searching this k, here are the current stats:

As always, no new prime.


All n < 4,600,000 have been tested.

Largest LLR-test currently running:
n = 4,790,000
FFT = 512k
7500 s / test
Caldwell entry rank: 274