xkcd #3137: Cursed Number

Title text:

Another group of mathematicians is working to put an upper bound on the number, although everyone keeps begging them to stop.

Transcript:

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Source: https://xkcd.com/3137/

explainxkcd for #3137

Another group of mathematicians is working to put an upper bound on the number, although everyone keeps begging them to stop.

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  • [–] 31 points 1 year ago* (last edited 1 year ago) (6 children)

    Felt like noodling a little with some numbers. I have a nice candidate. 22301. Pretty small, right? It's prime. That's not troubling to most anyone's sanity. Edit: one should check one's silly code more carefully before madly pretending to be mad on the Internet. It is not prime. But the intermediate numbers still are.

    There's something that can be done to that number four times (but no more) which results in a prime each time and the fourth step results in a 70 digit number that I may have looked at slightly tOo LoNnNg.

    Edit 2: Attempt at redemption for the math if not the joke: Start with 5497949 which is prime, and you can do the thing four times and get a prime each time. The last one has 108 digits and, no word of a lie, starts 6969...

    Imaginary bonus points for guessing what the heck the operation / something is.b

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  • [–] 23 points 1 year ago (3 children)

    But 22301 isn't prime? It's 29*769.

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  • [–] 34 points 1 year ago (2 children)

    Well, this is embarrassing. This is what I get for mathing after midnight.

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  • [–] 26 points 1 year ago (1 child)

    A moment of silence for all those who sacrificed themselves in the name of science

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  • [–] 14 points 1 year ago (4 children)

    The cursed number is pi. Everyone who tries to fully read it dies. This is why we shortened it to 3.14.

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    [–] 6 points 1 year ago (1 child)

    Sounds like the seed of an SCP.

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  • [–] 5 points 1 year ago (1 child)

    If a number is long enough human won't be able to perceive it all at once, so in fact there are only finite number of cases we need to check.

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  • [–] 9 points 1 year ago

    SCP-2.6*10^21^

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  • [–] 8 points 1 year ago

    Sounds like those stupid Rationalist cult groups who spend their time coming up with AI fantasies, and claim some thought-experiments are so powerful they'll ruin your mind - real immature stuff. Deserves to be lampooned like this.

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  • [–] 3 points 1 year ago (3 children)

    I'm confused, what is this new lower bound specifically?

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  • [–] 3 points 1 year ago

    Sure there's quite a lot of them to choose from, but for instance USPS tracking numbers are 22-digit numbers.

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  • [–] 3 points 1 year ago

    There really is an xkcd for everything.

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  • [–] 2 points 1 year ago

    This is why they invented notation. Just to be safe

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