‘‘I'm not much for knowing what's famous and what is not. It just doesn't seem that proving such a fact should be so hard.''

‘‘Really,'' I said. ‘‘Not so hard? Have you ever tried to prove it?''

‘‘No, but it seems that Jensen polynomials of the Riemann zeta function should be relevant. If you prove they have only real roots, wouldn't that be enough?''

‘‘Well, yes that is true,'' I said. ‘‘But we've known that for 90 years. Where did you study mathematics? You must have a PhD.''

‘‘I have never studied mathematics. I just enjoy reading about it. It's so abstract. The life of the mind and all that.'' She smiled, a faraway look in her eye.