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(Pardon if this seems a bit beginner, this is my first post in math - trying to improve my knowledge while tackling Project Euler problems)

I'm aware of Sigma notation, but is there a function/name for e.g.

$$ 4 + 3 + 2 + 1 \longrightarrow 10 ,$$

similar to $$4! = 4 \cdot 3 \cdot 2 \cdot 1 ,$$ which uses multiplication?

Edit: I found what I was looking for, but is there a name for this type of summation?

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    See [Faulhaber's formula](https://en.wikipedia.org/wiki/Faulhaber's_formula).2017-01-12
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    I like to call it "additorial" or "sumitorial" :)2018-04-23
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    @AlexM. absolutely not. He's asking for a term, not a proof of an equality.2018-10-31
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    @TheGreatDuck: That post contains the required term, too. Reading it also gives an answer to this question. Keep in mind that on StackExchange sites "duplicate" does not mean "exact duplicate", but rather "loose duplicate".2018-10-31
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    @AlexM. That's a stupid reason to mark as duplicate though. When something is marked as duplicate the test says "marked as **exact** duplicate". Has that been revised since I last saw it?2018-10-31
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    @TheGreatDuck: Needlessly calling people "stupid" is not the best approach in life. Anyway, the problem of whether to interpret the word "duplicate" in a strict or loose sense has caused a lot of discussion, proof that it is not a simple one. For a start, go patiently through the answers given [here](https://math.meta.stackexchange.com/q/23458) and [here](https://math.meta.stackexchange.com/q/18917). I also believe that battling the closure of some random post is not the most helpful thing to do on MSE.2018-11-01

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