How about ANY FINITE SEQUENCE AT ALL?

  • juliebean@lemm.ee
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    13 days ago

    no. it merely being infinitely non-repeating is insufficient to say that it contains any particular finite string.

    for instance, write out pi in base 2, and reinterpret as base 10.

    11.0010010000111111011010101000100010000101...
    

    it is infinitely non-repeating, but nowhere will you find a 2.

    i’ve often heard it said that pi, in particular, does contain any finite sequence of digits, but i haven’t seen a proof of that myself, and if it did exist, it would have to depend on more than its irrationality.

    • tetris11@lemmy.ml
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      13 days ago

      Isnt this a stupid example though, because obviously if you remove all penguins from the zoo, you’re not going to see any penguins

      • untorquer@lemmy.world
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        13 days ago

        The explanation is misdirecting because yes they’re removing the penguins from the zoo. But they also interpreted the question as to if the zoo had infinite non-repeating exhibits whether it would NECESSARILY contain penguins. So all they had to show was that the penguins weren’t necessary.

        By tying the example to pi they seemed to be trying to show something about pi. I don’t think that was the intention.

        • juliebean@lemm.ee
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          13 days ago

          i just figured using pi was an easy way to acquire a known irrational number, not trying to make any special point about it.

          • untorquer@lemmy.world
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            10 days ago

            Yeah i got confused too and saw someone else have the same distraction.

            It makes sense why you chose that.

            This kind of thing messed me up so much in school 😂

      • Lanthanae@lemmy.blahaj.zone
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        13 days ago

        Its not stupid. To disprove a claim that states “All X have Y” then you only need ONE example. So, as pick a really obvious example.

        • Umbrias@beehaw.org
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          13 days ago

          it’s not a good example because you’ve only changed the symbolic representation and not the numerical value. the op’s question is identical when you convert to binary. thir is not a counterexample and does not prove anything.

          • orcrist@lemm.ee
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            13 days ago

            Please read it all again. They didn’t rely on the conversion. It’s just a convenient way to create a counterexample.

            Anyway, here’s a simple equivalent. Let’s consider a number like pi except that wherever pi has a 9, this new number has a 1. This new number is infinite and doesn’t repeat. So it also answers the original question.

            • Umbrias@beehaw.org
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              13 days ago

              “please consider a number that isnt pi” so not relevant, gotcha. it does not answer the original question, this new number is not normal, sure, but that has no bearing on if pi is normal.