Inverse Sum Cubed
Calculus
Level
4
\[\large\displaystyle\sum_{n=1}^{\infty} \left({\displaystyle\sum_{k=0}^nk^3} \right)^{-1} \]
If the value of the series above can be expressed as \(\dfrac{a\pi^2}b-c\) where \(a,b,c\) are positive integers, and \(a,b\) are coprime to each other, find the value of \(a+b+c\).
See Also Inverse Sum and Inverse Sum Squared.
by
Ikkyu San