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quasar987
Dec9-04, 05:32 PM
Leibniz criterion for alterning serie say that if the two conditons a_n >0 is decreasing and -->0 are satisfied, the serie converges. It doesn't say that if they don't it diverge.

So how do you determine the convergence of an alternative serie that doesn't satisfy the conditions? For exemple,

\sum_{n=1}^{\infty} (-1)^n\frac{1}{n^{1/n}}

a_n \rightarrow 1 \neq 0

Hurkyl
Dec9-04, 05:35 PM
So, you're asking what test to use when the terms don't converge to 0?

quasar987
Dec9-04, 05:40 PM
Yeah, a test, ok.. maybe I should have tought about this one a little longer. :/