Erdős number

A low Erdős number is a status symbol among 20th century mathematicians and is similar to the 6-degrees-of-separation concept.

Let $e(p)$ be the Erdős number of person $p$. Your Erdős number is

• 0 if you are Paul Erdős

• $\min \{e(x)|x\in X\}+1$, where $X$ is the set of all persons you have authored a paper with.