Let the positive series ∑ UN diverge and Sn be the partial sum sequence of UN. It is proved that the series ∑ UN / Sn ^ 2 converges
Positive series
SN-S (n-1) = UN > 0, that is, Sn > s (n-1),
So UN / Sn ^ 2
Positive series
SN-S (n-1) = UN > 0, that is, Sn > s (n-1),
So UN / Sn ^ 2