Hacker News Reader

The Physicist proof all odd numbers are prime: 1 is prime, 3 is prime, 5 is prime, 7 is prime, 9 is experimental error, 11 is prime, 13 is prime...

I worry about anyone who believes that 1 is prime :(

It makes for a much better joke if you start at one ;-)

It is actually a pretty old joke, there are a few variations on it (one for Computer Scientists, one for Mathematicians, etc...):

Oh, I recognize the joke, but I still worry about any engineers who believe that 1 is prime :)