Using (Cesàro), calculate the limit of the sequence $\left( v _ { n } \right) _ { n \geqslant 1 }$ defined by $v _ { n } = \sum _ { k = 1 } ^ { n } \frac { 1 } { k n }$. Then, using a series-integral comparison, give an equivalent of $\left( v _ { n } \right) _ { n \geqslant 1 }$.