Melin transform of the floor function [x]

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Homework Statement
using analytic continuation can i compute the mellin transform of the floor function as a riemann zeta function
Relevant Equations
$$ \int_{0}^{\infty}[x]x^{s-1}= - \frac{\zeta (-s)}{s} $$
usig analytic continuation and mellin transform properties
 
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How do you define [z] for z \in \mathbb{C}?
 
Rfael said:
Relevant Equations: $$ \int_{0}^{\infty}[x]x^{s-1}= - \frac{\zeta (-s)}{s} $$
Just a small quibble: although the meaning of your integral is clear from the context of your equation, please don't forget to always explicitly include the differential of the variable you're integrating over:$$\int_{0}^{\infty}[x]x^{s-1}dx$$
 
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Your question could have been phrased more clearly.

Try evaluating your integral by first expressing it as ##\sum_{n=0}^\infty \int_n^{n+1} [x] x^{s-1} dx## and then writing out the resulting series. That should make the connection to ##\zeta (-s)## clear—if that's what you're aiming for.
 
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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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