Primes in ϕ (phi) - Page 2

ericw · 2017-02-20, 12:13

Cool. Thanks for the update!

rogue · 2017-03-03, 12:33

Searched to 300,000 and no new PRPs. Continuing.

rogue · 2017-03-07, 01:31

The previous post should have been to 400,000, not 300,000. Completed to 500,000. I am now using a four core machine, but each test is taking 3+ hours.

rogue · 2017-03-12, 13:20

Completed to 600,000 and continuing. Tests are now taking over 5 hours each.

rogue · 2017-03-19, 13:47

Completed to 700,000 and continuing. Tests are now taking over 7 hours each.

J F · 2017-03-19, 16:47

Quote:

Originally Posted by rogue

Completed to 600,000 and continuing. Tests are now taking over 5 hours each.

*scratch head* I don't unterstand these numbers.
5+ hours for a test at this range sounds like
something older, maybe slow 1st-gen AVX.
Assuming >2K numbers per 100K range after sieving
gives >10K CPU-hours, yet you do 100K in a week.
What machine is that?

rogue · 2017-03-19, 17:15

Quote:

Originally Posted by J F

*scratch head* I don't unterstand these numbers.
5+ hours for a test at this range sounds like
something older, maybe slow 1st-gen AVX.
Assuming >2K numbers per 100K range after sieving
gives >10K CPU-hours, yet you do 100K in a week.
What machine is that?

You are correct. I was mistaken. I just realized that my inputs are not sorted by ascending number of decimal digits, but that is not correct. This is due to how I split the file into four files. I'll let the current tests complete, clear them out, sort the inputs, then restart.

rogue · 2017-04-09, 14:11

Now that I sorted my input list correctly, I can safely say that this is completed to 300,000 decimal digits. I'm continuing.

rogue · 2017-04-24, 13:24

Completed to 400,000 decimal digits with no new prime. Continuing.

rogue · 2017-06-20, 21:20

Completed to 500,000 with no new primes. I'm stopping. I'll post a pre-sieved file of candidates later if someone wants to take this further.

Batalov · 2017-06-21, 04:39

There is a similar sequence for φ-1 (or 1/φ as it were): A065868
Perhaps, I can add a few terms to it...

2017-03-03, 12:33	#13
rogue "Mark" Apr 2003 Between here and the 11·577 Posts	Searched to 300,000 and no new PRPs. Continuing. Last fiddled with by rogue on 2017-03-03 at 12:43

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2017-02-20, 12:13	#12
ericw Oct 2015 19 Posts	Cool. Thanks for the update!

2017-03-07, 01:31	#14
rogue "Mark" Apr 2003 Between here and the 11·577 Posts	The previous post should have been to 400,000, not 300,000. Completed to 500,000. I am now using a four core machine, but each test is taking 3+ hours.

2017-03-12, 13:20	#15
rogue "Mark" Apr 2003 Between here and the 18CB₁₆ Posts	Completed to 600,000 and continuing. Tests are now taking over 5 hours each.

2017-03-19, 13:47	#16
rogue "Mark" Apr 2003 Between here and the 14313₈ Posts	Completed to 700,000 and continuing. Tests are now taking over 7 hours each.

2017-04-09, 14:11	#19
rogue "Mark" Apr 2003 Between here and the 1100011001011₂ Posts	Now that I sorted my input list correctly, I can safely say that this is completed to 300,000 decimal digits. I'm continuing.

2017-04-24, 13:24	#20
rogue "Mark" Apr 2003 Between here and the 11·577 Posts	Completed to 400,000 decimal digits with no new prime. Continuing.

2017-06-20, 21:20	#21
rogue "Mark" Apr 2003 Between here and the 11×577 Posts	Completed to 500,000 with no new primes. I'm stopping. I'll post a pre-sieved file of candidates later if someone wants to take this further.

2017-06-21, 04:39	#22
Batalov "Serge" Mar 2008 Phi(4,2^7658614+1)/2 3⁶×13 Posts	There is a similar sequence for φ-1 (or 1/φ as it were): A065868 Perhaps, I can add a few terms to it...