[Jakob Bernoulli]
Jakob Bernoulli 证明了
\[
\sum_{k=1}^{\infty}\frac{k^2}{2^k}=6,\quad\sum_{k=1}^{\infty}\frac{k^3}{2^k}=26.
\]
James A. Sellers, The infinite series of Euler and the Bernoulli's spice up a calculus class
Answer
Jakob Bernoulli 证明了
\[
\sum_{k=1}^{\infty}\frac{k^2}{2^k}=6,\quad\sum_{k=1}^{\infty}\frac{k^3}{2^k}=26.
\]
James A. Sellers, The infinite series of Euler and the Bernoulli's spice up a calculus class