this post was submitted on 17 May 2024
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Unexpected Factorial

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When you use an exclamation mark with a number, you’re actually implying it’s not a normal number any more. It’s a factorial!

Ok, so how does this work?

5!=1×2×3×4×5=120

6!=720

These numbers get really large. For example:

15!≈1.3×10^12

So, next time you see a headline with 2000! in it, you’ll know what to expect.

There are also double factorials (n!!) and iterated factorials (n!)!, and they aren’t the same thing. Just add more exclamation marks and you get multifactorial. Check wikipedia to see how spicy it gets.

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September 24! (sopuli.xyz)
submitted 10 months ago* (last edited 10 months ago) by [email protected] to c/[email protected]
 

Now September has about 6.2*10^23 days, which is several orders of magnitude longer than the age of the known universe.

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[–] [email protected] 9 points 10 months ago
[–] [email protected] 2 points 5 months ago (1 children)

Well it was available for a whole 4! days before they realized and took it back offline for rerelease in 24! days! I can't wait!

[–] [email protected] 1 points 5 months ago

It was a wild ride. I enjoyed reading some articles about it.