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 2021-05-03, 07:40 #12 bur     Aug 2020 5*10398e-4;3*2539e-3 3×131 Posts 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... Last fiddled with by bur on 2021-05-03 at 07:49
 2021-05-29, 07:06 #13 bur     Aug 2020 5*10398e-4;3*2539e-3 3·131 Posts 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 Last fiddled with by bur on 2021-05-29 at 07:08
 2021-06-11, 10:59 #14 bur     Aug 2020 5*10398e-4;3*2539e-3 1100010012 Posts 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)
 2021-07-20, 17:31 #15 bur     Aug 2020 5*10398e-4;3*2539e-3 3·131 Posts 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.
 2021-08-27, 17:14 #16 bur     Aug 2020 5*10398e-4;3*2539e-3 6118 Posts 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 Last fiddled with by bur on 2021-08-27 at 17:15

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