Primes in π - Page 19

ATH · 2017-07-04, 15:09

Remaining 5,376 pi prime candidates 750K-1M digits sieved to 245G plus a tiny bit higher non-consecutive ranges:
picandidates750K-1M.txt

davar55 · 2018-03-30, 19:56

Any progress on this curious number a(20)?
What's the likelihood that a 750k-1M digit candidate will be a PRP?
Or that all of the candidates in that range will be composite?

J F · 2018-03-31, 01:02

Quote:

Originally Posted by davar55

Any progress on this curious number a(20)?
What's the likelihood that a 750k-1M digit candidate will be a PRP?
Or that all of the candidates in that range will be composite?

#20 at 833K digits atm, no PRP.
Quick (and very rough) approximation that a random pick
with n decimal digits is prime: 1 : 2.3n
Chance to find none between 750K and 1M is around 90%.

davar55 · 2018-08-09, 13:24

Any news/progress on a(20)? If things continue as they're going, approximately
when will 1M digits be reached? How significant would the next trial value be,
if found probably prime?

davar55 · 2018-08-31, 20:44

Quote:

Originally Posted by J F

#20 at 833K digits atm, no PRP.
Quick (and very rough) approximation that a random pick
with n decimal digits is prime: 1 : 2.3n
Chance to find none between 750K and 1M is around 90%.

Thank you. I sometimes forget the niceties.

There's no way to know for sure (yet) that there is or isn't a prime located
at the position a(20) in pi. If there is, and it's relatively long, these efforts
to find it are interesting as will be the result. If there is no prime at that
position, proving which would probably be daunting, then we've hit on
an unusual numerical singularity.

paulunderwood · 2019-03-14, 12:46

You can now go up to 31.4 trillion digits

petrw1 · 2019-03-14, 19:03

...

petrw1 · 2019-03-14, 19:05

...

davar55 · 2019-03-19, 13:12

Quote:

Originally Posted by paulunderwood

You can now go up to 31.4 trillion digits

Wow. If a(20) grew that large, for the sake of argument, what resources would be
needed to prove a 31.4 trillion digit number prime (or probably prime)?

paulunderwood · 2019-03-19, 13:38

Quote:

Originally Posted by davar55

Wow. If a(20) grew that large, for the sake of argument, what resources would be
needed to prove a 31.4 trillion digit number prime (or probably prime)?

Deep Thought running Primo? Probably to the end of time!

davar55 · 2019-03-19, 14:15

Quote:

Originally Posted by paulunderwood

Deep Thought running Primo? Probably to the end of time!

I don't doubt Deep Thought's abilities, but Hal could probably do it in half that time.

2019-03-14, 12:46	#204
paulunderwood Sep 2002 Database er0rr 3·11·107 Posts	You can now go up to 31.4 trillion digits Last fiddled with by paulunderwood on 2019-03-14 at 12:47

2019-03-14, 19:03	#205
petrw1 1976 Toyota Corona years forever! "Wayne" Nov 2006 Saskatchewan, Canada 2³×3⁴×7 Posts	Wife of Pi ... Attached Thumbnails

2019-03-14, 19:05	#206
petrw1 1976 Toyota Corona years forever! "Wayne" Nov 2006 Saskatchewan, Canada 2³·3⁴·7 Posts	Pi In trouble. ... Attached Thumbnails

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2017-07-04, 15:09	#199
ATH Einyen Dec 2003 Denmark 3·17·59 Posts	Remaining 5,376 pi prime candidates 750K-1M digits sieved to 245G plus a tiny bit higher non-consecutive ranges: picandidates750K-1M.txt

2018-03-30, 19:56	#200
davar55 May 2004 New York City 2³·23² Posts	Any progress on this curious number a(20)? What's the likelihood that a 750k-1M digit candidate will be a PRP? Or that all of the candidates in that range will be composite?

2018-08-09, 13:24	#202
davar55 May 2004 New York City 2³·23² Posts	Any news/progress on a(20)? If things continue as they're going, approximately when will 1M digits be reached? How significant would the next trial value be, if found probably prime?