Does this infinite series make sense ?

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SUMMARY

The infinite series g(x) = ∑(a_n/√(x-n)) does not converge for any real value of x due to the presence of negative terms under the square root as n approaches infinity. This results in g(x) becoming complex for all positive integers n, regardless of the chosen x. Approximating the series with the integral ∫(a(r)(x-r)^{-1/2}) dr leads to similar conclusions, indicating that the series is mathematically valid but yields complex results. The convergence of the series is contingent upon the behavior of the coefficients a_n.

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mhill
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given the series

[tex]g(x)= \sum_{n=0}^{\infty}\frac{a_{n}}{\sqrt {x-n}}[/tex]

where the coefficients a_n are real numbers my question is does the above makes sense ? i mean since we are summing over all positive integers , no matter how big we choose 'x' there will be a factor so x-n n=0,1,2,3,4,..... (x-n) <0 then g(x) is complex no matter what real x we put.

If we approximate the series by an integral [tex]\int_{0}^{\infty}dr a(r) (x-r)^{-1/2}[/tex] we get a similar result, i do not know if this is paradoxical and i should have taken the absolute value |x| inside the square root.
 
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It makes sense mathematically. You end up with a complex function. Convergence may be another matter - depending on the behavior of an.
 

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