Summation Identity for i^p power question, really simple

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Homework Statement




\sum_{i=0}^{n} i^{p} = \frac {(n+1)^{p+1}}{p+1} + \sum_{k=1}^{p} \frac {B_{k}}{p-k+1} (^{p}_{k}) (n+1)^{p-k+1}


where Bk is a Bernoulli number.

There is no actual question here I would just like to know if this formula is for sums of i to any power, of course its rather cumbersome but the question still stands. All I want to know is if I understand what it is doing.

edit: oh and

(^{p}_{k}) = \frac {p!}{k!(p-k)!} \;\; 0 \leq k \leq p
 
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Yes, that is called Faulhaber's formula and is valid for natural numbers p.
 
Incidentally, there is a better way to make binomial coefficients than (^p_k), which will always produce "small" binomial coefficients and won't always place the arguments gracefully with respect to the parentheses. You can write \binom{p}{k} to get \binom{p}{k}.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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