New posts in Bell Numbers

Compact formula for the $n$th derivative of $f\left(\sqrt{x+1}\right)$?

Compute $S_n=\sum\limits_{a_1,a_2,\cdots,a_n=1}^\infty \frac{a_1a_2\cdots a_n}{(a_1+a_2+\cdots+a_n)!}$

How are the Bell numbers related to this exponential series?

Partitions and Bell numbers