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garryh22
Apr8-08, 05:58 AM
1. The problem statement, all variables and given/known data

ln((n!e^n)/n^(n+1/2))

2. Relevant equations

Does the series above converge or diverge.

3. The attempt at a solution

I can see that it diverges but I'm looking for the appropriate test to show this
1. The problem statement, all variables and given/known data



2. Relevant equations



3. The attempt at a solution

Roberto Bramb
Apr8-08, 06:31 AM
The series is convergent by Cauchy criterium since C(n+1)/C(n)->0 for n>infinity,
as can be easily verified using Striling formula : log(n!) => n*log(n)-n

garryh22
Apr8-08, 07:10 AM
Thanks a great deal. I never heard of the Striling formula till now. I just looked it up, applied it and the expression reduced to ln(1/n)^(1/2) which diverges with p-series. Further insight would be greatly appreciated