Evaluate Gamma Integral: j,k Positive Constants

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mmzaj
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greetings . any ideas on how to evaluate this integral

[tex]\lim_{T\rightarrow \infty}\frac{1}{2T}\int_{-T}^{T}\frac{\Gamma(3+it)}{\Gamma(3+it-j)}e^{ikt}dt[/tex]

[itex]j, k[/itex] are positive constants .
 
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mmzaj said:
greetings . any ideas on how to evaluate this integral

[tex]\lim_{T\rightarrow \infty}\frac{1}{2T}\int_{-T}^{T}\frac{\Gamma(3+it)}{\Gamma(3+it-j)}e^{ikt}dt[/tex]

[itex]j, k[/itex] are positive constants .

Hi !
this integral cannot be evaluated for T-->infinity because it is not convergent.
 

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mmzaj said:
greetings . any ideas on how to evaluate this integral

[tex]\lim_{T\rightarrow \infty}\frac{1}{2T}\int_{-T}^{T}\frac{\Gamma(3+it)}{\Gamma(3+it-j)}e^{ikt}dt[/tex]

[itex]j, k[/itex] are positive constants .

Not sure, but would a Fourier transform help here?
 
KarmonEuloid said:
Not sure, but would a Fourier transform help here?
I don't think so. Since the integral is not convergent for T tending to infinity, the Fourier transform is of no help to find a limit which doesn't exist anyways.

mathman said:
The gamma function ratio is a polynomial in t (degree = j, if j is an integer).
This is a so-called Pochhammer polynomial.