# Inspired by the oldest problem on brilliant

$A=\sum _{n=1}^{\infty }\frac{\left(-1\right)^nd\left(n\right)}{n^2}$

Find $$\left\lfloor 10000A \right\rfloor$$

Note: $$d(n)$$ denotes the number of positive integer divisors of $$n$$.

Context

×