I've to study this series:
$\sum_{n=1}^\infty e^{\sqrt n\,x}$
My teacher wrote that with the asymptotic comparison with this series:
$\sum_{n=1}^\infty\frac{1}{n^2}$
My series converges for every
$x<0$
I don't understand the motivation, hoping for someone to enlighten me!
=) Thanks. Leonardo.