View Full Version : Zeta function and summation convergence
rman144
Jun27-09, 02:50 PM
I need to know if the following series converges:
∑(k=1 to k=oo)[(((-1)^k) ζ(k))/(e^k)]
The problem is that zeta(1)=oo; however, the equation satisfies the conditions of convergence for an alternating series [the limit as k->oo=0 and each term is smaller than the last.]
Any thoughts?
*-<|:-D=<-<
Jun27-09, 03:52 PM
How did you arrive at the sum?
camilus
Jun27-09, 05:53 PM
well yeah I see what you're saying about zeta of 1. To see if the summation converges, try one of the tests, like tha ratio test.
g_edgar
Jun28-09, 08:01 AM
I need to know if the following series converges:
∑(k=1 to k=oo)[(((-1)^k) ζ(k))/(e^k)]
The problem is that zeta(1)=oo; however, the equation satisfies the conditions of convergence for an alternating series [the limit as k->oo=0 and each term is smaller than the last.]
Any thoughts?
This one converges
\sum_{k=2}^\infty \frac{(-1)^k \zeta(k)}{e^k}
But in the original zeries, the k=1 term is the problem.
*-<|:-D=<-<
Jun28-09, 04:18 PM
Yes if memory serves me right that sum is just a constant and an x away from being a taylor series of the digamma function.
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