Question 2
Let $a_1,a_2,\ldots$ be real numbers satisfying $a_{i+j}\le a_i+a_j$ for all positive integers $i,j$. Prove that
$$a_1+\frac{a_2}{2}+\frac{a_3}{3}+\cdots+\frac{a_n}{n}\ge a_n$$
for every positive integer $n$.
$$a_1+\frac{a_2}{2}+\frac{a_3}{3}+\cdots+\frac{a_n}{n}\ge a_n$$
for every positive integer $n$.