Re:What is the largest bi-truncatable prime?
by tomxor on Friday May 03, 2019 @09:02AM
(#19818000)
I find it difficult be interested in these, primes are primes; bi-truncatable are base-10 specific. It feels more like numerology in the same way that we assign meaning to powers of 10 and the natural world does not.
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Re:What is the largest bi-truncatable prime?
by tedunangst on Friday May 03, 2019 @10:20AM
(#19818661)
"What's the smallest power of pi that spells your name when encoded in base64?"
Re:What is the largest bi-truncatable prime?
by enriquto on Friday May 03, 2019 @11:02AM
(#19819035)
There's probably an infinite set of such powers inside any neighborhood of zero.
Re:What is the largest bi-truncatable prime?
by hervature on Friday May 03, 2019 @12:57PM
(#19820095)
I was going to say, that irrationality would mean that any power of pi would contain your name given enough digits.
That logic is incorrect. The base 2 Liouville number (https://en.wikipedia.org/wiki/Liouville_number) is transcendental, so surely irrational, but mostly contains two repeated characters.
Re:What is the largest bi-truncatable prime?
by Analemma_ on Friday May 03, 2019 @05:19PM
(#19822379)
That’s not true. To prove that any digit sequence will eventually appear, you need to show the number is normal (https://en.wikipedia.org/wiki/Normal_number), which is much, much harder to prove than being irrational or even transcendental. It has pretty much only been done for numbers specifically constructed to be normal, and so not including pi.
Re:What is the largest bi-truncatable prime?
by contravariant on Friday May 03, 2019 @09:55PM
(#19823796)
Strictly speaking that property hasn't been proven of pi (nor whether this would still hold for powers of pi). As you may have gathered irrationality is a weaker property.
Irrationality would be enough to guarantee that you can find a power where your name is right at the start. You do need log(pi)/log(10) (or whatever base you're using) to be irrational for that to work, but I think you can prove that using the fact that pi is transcendental.
I don't think anyone is trying to ascribe any meaning to this.. like the name of the site implies, it's just a puzzle.