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Old 2017-07-04, 15:09   #199
ATH
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Remaining 5,376 pi prime candidates 750K-1M digits sieved to 245G plus a tiny bit higher non-consecutive ranges:
picandidates750K-1M.txt
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Old 2018-03-30, 19:56   #200
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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?
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Old 2018-03-31, 01:02   #201
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Quote:
Originally Posted by davar55 View Post
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%.
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Old 2018-08-09, 13:24   #202
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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?
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Old 2018-08-31, 20:44   #203
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Quote:
Originally Posted by J F View Post
#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.
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Old 2019-03-14, 12:46   #204
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You can now go up to 31.4 trillion digits

Last fiddled with by paulunderwood on 2019-03-14 at 12:47
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Old 2019-03-14, 19:03   #205
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Old 2019-03-14, 19:05   #206
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Old 2019-03-19, 13:12   #207
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Quote:
Originally Posted by paulunderwood View Post
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)?
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Old 2019-03-19, 13:38   #208
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Quote:
Originally Posted by davar55 View Post
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!
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Old 2019-03-19, 14:15   #209
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Quote:
Originally Posted by paulunderwood View Post
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.
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