Thread: Primes in π
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Old 2018-03-31, 01:02   #201
J F's Avatar
Sep 2013

23×7 Posts

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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