this post was submitted on 26 Dec 2024
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How about ANY FINITE SEQUENCE AT ALL?

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[โ€“] putoelquelolea@lemmy.ml 4 points 12 hours ago (1 children)

My guess would be that - depending on the number of digits you are looking for in the sequence - you could calculate the probability of finding any given group of those digits.

For example, there is a 100% probability of finding any group of two, three or four digits, but that probability decreases as you approach one hundred thousand digits.

Of course, the difficulty in proving this hypothesis rests on the computing power needed to prove it empirically and the number of digits of Pi available. That is, a million digits of Pi is a small number if you are looking for a ten thousand digit sequence

[โ€“] Melatonin@lemmy.dbzer0.com 2 points 12 hours ago (1 children)

But surely given infinity, there is no problem finding a number of ANY length. It's there, somewhere, eventually, given that nothing repeats, the number is NORMAL, as people have said, and infinite.

The probability is 100% for any number, no matter how large, isn't it?

Smart people?

[โ€“] putoelquelolea@lemmy.ml 1 points 10 hours ago

In theory, sure. In practice, are we really going to find a series of ten thousand ones? I would also like to hear more opinions from smart people

[โ€“] vrighter@discuss.tchncs.de 26 points 1 day ago (1 children)

it's actually unknown. It looks like it, but it is not proven

[โ€“] HiddenLayer555@lemmy.ml 10 points 1 day ago (2 children)

Also is it even possible to prove it at all? My completely math inept brain thinks that it might be similar to the countable vs uncountable infinities thing, where even if you mapped every element of a countable infinity to one in the uncountable infinity, you could still generate more elements from the uncountable infinity. Would the same kind of logic apply to sequences in pi?

[โ€“] AHemlocksLie@lemmy.zip 7 points 1 day ago

Man, you're giving me flashbacks to real analysis. Shit is weird. Like the set of all integers is the same size as the set of all positive integers. The set of all fractions, including whole numbers, aka integers, is the same size as the set of all integers. The set of all real numbers (all numbers including factions and irrational numbers like pi) is the same size as the set of all real numbers between 0 and 1. The proofs make perfect sense, but the conclusions are maddening.

[โ€“] zeca@lemmy.eco.br 1 points 21 hours ago

its been proven for some other numbers, but not yet for pi.

[โ€“] Yoddel_Hickory@lemmy.ca 44 points 1 day ago (7 children)

This is what allows pifs to work!

[โ€“] somenonewho@feddit.org 1 points 19 hours ago

Thanks. I love these kind of fun OpenSource community projects/ideas/jokes whatever. The readme reminds me of ed

[โ€“] db0@lemmy.dbzer0.com 8 points 1 day ago* (last edited 1 day ago)

Thats very cool. It brings to mind some sort of espionage where spies are exchanging massive messages contained in 2 numbers. The index and the Metadata length. All the other spy has to do is pass it though pifs to decode. Maybe adding some salt as well to prevent someone figuring it out.

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[โ€“] nul42@lemmy.ca 17 points 1 day ago

It has not been proven either way but if pi is proven to be normal then yes. https://en.m.wikipedia.org/wiki/Normal_number

[โ€“] SwordInStone@lemmy.world 77 points 2 days ago* (last edited 1 day ago) (16 children)

No, the fact that a number is infinite and non-repeating doesn't mean that and since in order to disprove something you need only one example here it is: 0.1101001000100001000001... this is a number that goes 1 and then x times 0 with x incrementing. It is infinite and non-repeating, yet doesn't contain a single 2.

[โ€“] bradorsomething@ttrpg.network 1 points 21 hours ago (1 children)

1/3 is infinite in decimal form, as a more common example. 0.333333333โ€ฆ.

[โ€“] SwordInStone@lemmy.world 4 points 20 hours ago
[โ€“] GreyEyedGhost@lemmy.ca 35 points 1 day ago (1 children)

This proves that an infinite, non-repeating number needn't contain any given finite numeric sequence, but it doesn't prove that an infinite, non-repeating number can't. This is not to say that Pi does contain all finite numeric sequences, just that this statement isn't sufficient to prove it can't.

[โ€“] SwordInStone@lemmy.world 13 points 1 day ago

you are absolutely right.

it just proves that even if Pi contains all finite sequences it's not "since it oa infinite and non-repeating"

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[โ€“] lily33@lemm.ee 163 points 2 days ago* (last edited 2 days ago) (15 children)

It's almost sure to be the case, but nobody has managed to prove it yet.

Simply being infinite and non-repeating doesn't guarantee that all finite sequences will appear. For example, you could have an infinite non-repeating number that doesn't have any 9s in it. But, as far as numbers go, exceptions like that are very rare, and in almost all (infinite, non-repeating) numbers you'll have all finite sequences appearing.

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