MathDB
Problems
Contests
Undergraduate contests
VTRMC
1979 VTRMC
6
1979 VTRMC #6
1979 VTRMC #6
Source:
August 8, 2018
algebra
Problem Statement
Suppose
a
n
>
0
a _ { n } > 0
a
n
>
0
and
∑
n
=
1
∞
a
n
\sum _ { n = 1 } ^ { \infty } a _ { n }
∑
n
=
1
∞
a
n
diverges. Determine whether
∑
n
=
1
∞
a
n
/
S
n
2
\sum _ { n = 1 } ^ { \infty } a _ { n } / S _ { n } ^ { 2 }
∑
n
=
1
∞
a
n
/
S
n
2
converges, where
S
n
=
a
1
+
a
2
+
⋯
+
a
n
.
S _ { n } = a _ { 1 } + a _ { 2 } + \dots + a _ { n } .
S
n
=
a
1
+
a
2
+
⋯
+
a
n
.
Back to Problems
View on AoPS