Warning: we brake for number theory
If any Silicon Valley drivers have found that traffic is moving more slowly than usual these days on the southbound 101 right around Ralston...

In other words, the billboard (which offers problem-solvers the URL to, sorry, a page containing an even harder problem), is a recruiting campaign. We've always worked hard to hire the smartest engineers we can find, and we thought this would be a cool way to find a few more. Perhaps including you. If you're a math or computer whiz who doesn't happen to live within shouting distance of Palo Alto -- good luck, and we're looking forward to hearing from you.
- A. Googler