Question 73
$$
\sum_{n=2009}^{\infty} \frac{1}{\binom{n}{2009}}
$$
Note that $\binom{n}{k}$ is defined as $\frac{n!}{k!(n-k)!}$.
\sum_{n=2009}^{\infty} \frac{1}{\binom{n}{2009}}
$$
Note that $\binom{n}{k}$ is defined as $\frac{n!}{k!(n-k)!}$.
MathNet 2009-part-05 — 172 problems (EN–VI) Question 73
Math Olympiad Vault · MathNet 2009-part-05 — 172 problems (EN–VI)