this post was submitted on 08 Nov 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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Which is about 1.2*10^17. Makes me feel very young now that I see how old some Lemmy users are.

Just for reference, the age of the universe is estimated to be around 13.787 *10^9 years.

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[–] Dadifer@lemmy.world 11 points 1 year ago
[–] affiliate@lemmy.world 9 points 1 year ago (1 children)

is this another piece of evidence in favor of the cyclical universe theory?

[–] Hamartiogonic@sopuli.xyz 4 points 1 year ago

Cyclical universe confirmed! No further questions.

[–] Stalinwolf@lemmy.ca 5 points 1 year ago

Tipping into my late '30s here. I often see much older folks making themselves known here. I don't know if that explains the more civil (mostly) environment, or if other demographics contribute to this. I will note that the US election season really stirred the pot and kicked a few hornet nests. Hoping that subsides a bit, but doubtful. Either way, I feel a lot more respected on this platform and no longer have the desire to be confrontational with others.

[–] tkk13909@sopuli.xyz 3 points 1 year ago

Small world huh? Leo follows me and just showed up on my feed. I swear Fedi has an algorithm sometimes.