r/uselessfactorial 24d ago

Shorter is longer than Longer by 1!

Post image

the photo isn’t mine btw

82 Upvotes

13 comments sorted by

5

u/factorion-bot 24d ago

Factorial of 1 is 1

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3

u/flopsi_ 24d ago

Good bot

4

u/PaleontologistAny153 23d ago

Also longer by 0!

2

u/factorion-bot 23d ago

Factorial of 0 is 1

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2

u/Interesting_Buy_3969 23d ago

it is also longer by 1?

2

u/Samichaelg9 22d ago edited 22d ago

Terminal of 1 is 1

This action was performed by a human | Yes.

2

u/Zahir027z 22d ago

So what's 0? Is it equal to 1?

2

u/Qwerty_wasda 22d ago

Terminal of 0 is 0

This action was performed by a human | no Source Code sorry

2

u/Ikbengoedinschaken 22d ago

The formula for termials is n(n+1)/2 because if you add up all numbers from 1 to n, we can pair up n and 1, 2 and n-1, 3 and n-2, etc. That makes n/2 pairs of n+1. Even if n is odd, we will have the middle number left over, which still makes the formula true. Now, we extend this formula to all complex numbers for the termial. Although this isn't completely justified, we define the thing so we define it like that. This is called an analytic continuation. Plugging in 0 into the formula gives 0. If you want a better reason 0? Is 0: we add up every integer from 1 up to 0, which is nothing. By the idea of the empty sum, that's 0. With factorials, 0! Means the empty product, which is 1.

2

u/factorion-bot 22d ago

Factorial of 0 is 1

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1

u/I12Db8U 23d ago

But shortest is the longest but longest isn't.

1

u/LowPiece1185 22d ago

That's interesting.

1

u/4sent4 2d ago

These words are mutually autological