I've developed high-performance medical imaging applications. I've build large distributed financial systems. I've built 2D/3D games. I've done a ton of stuff. Hell, I'm a software engineering hiring manager at my company. Yet I have no idea what a Pascall's triangle is, or how to give you a row of them.
I consider questions like that to be as useless as brainteasers in determining whether or not to hire someone. Sure, it can help give clues about a candidate, but if you're seriously considering rejecting a candidate on that point alone, I think you've got a problem in your hiring process.